Purpose: Problem: Tibia plateau fractures may lead to end-stage post-traumatic arthritis that requires reconstructive surgery. The incidence of this problem is unknown but has been estimated at 20–40% by studies that were limited by small sample sizes, potential follow-up bias, and the limitations of using radiographic arthritis as a chosen outcome (not correlated to function). The use of administrative data bases to follow the care of a large number patients for robust end points such as surgery, offers an opportunity to address these limitations. Purpose: to determine the minimum ten year incidence of post-traumatic arthritis necessitating reconstructive surgery following tibia plateau fractures.

Method: We queried our prospectively collected Orthopedic Trauma Data base to identify operatively treated patients with tibia plateau fractures. These cases were cross-referenced with the data from our Province’s administrative health database and tracked over time for the performance of reconstructive knee surgery. Each individual’s exposure/follow-up period was limited by end of health plan coverage on record or date of death from vital statistics data. The minimum follow-up was ten years.

Results: Between 1987 and 1994, 378 patients with a tibia plateau fracture were treated at our institution. The average age was 46 years (sd=18, range 14–87), while 56% of patients were males. Seventeen out-of-Province residents were excluded, along with forty-six others whose “Medical Services Plan” numbers could not be identified. Of which seven were WCB patients and one who was affiliated with the military. The study cohort therefore consisted of 311 patients with 314 tibia plateau fractures. Four individuals (1.3%) we treated tibia plateau fractures have required reconstructive knee surgery for end-stage post-traumatic knee arthritis at 10 years. Of these 3 of 4 were type VI fractures and 1 of 4 was open.

Conclusion: Patients who require surgical treatment of tibia plateau fractures may be counseled on their long-term risk of requiring reconstructive knee surgery for endstage knee arthritis based on a clinical study. Based on our findings, the proportion of those who have required a total knee surgery, ten years following their injury, is lower than previously published.

A new generation of knee prostheses has been introduced with the intention of improving post-operative knee flexion. In order to evaluate whether this goal has been achieved we performed a systematic review and meta-analysis. Systematic literature searches were conducted on MEDLINE and EMBASE from their inception to December 2007, and proceedings of scientific meetings were also searched. Only randomised, clinical trials were included in the meta-analysis. The mean difference in the maximum post-operative flexion between the ‘high-flex’ and conventional types of prosthesis was defined as the primary outcome measure. A total of five relevant articles was identified.

Analysis of these trials suggested that no clinically relevant or statistically significant improvement was obtained in flexion with the ‘high-flex’ prostheses. The weighted mean difference was 2.1° (95% confidence interval −0.2 to +4.3; p = 0.07).

One hundred and thirty-one cemented femoral stems inserted during revision total hip arthroplasty were reviewed to determine component survival. Harris Hip scores and complete radiographs were analysed. Survival at 10.5 years was 86.9%. Radiographically, 76.9% of the remaining components were classified as stable or possibly loose. Chi-square analysis of demographic and surgical factors determined age < 60 years, male gender and stems > 200 mm in length contributed significantly to failure (p < 0.05). Contrary to published results, we found that longer stems were more susceptible to failure. Revision femoral THA to a cemented component is an effective procedure that exhibits good long-term survival.

The purpose of this study was to determine the long-term survival of cemented femoral components in revision total hip arthroplasty (THA) and to identify factors significant to implant failure.

Cemented femoral components demonstrate good long-term survival and remain a suitable option for revision THA for hips with an intact cortical tube.

We report high long-term survival for this increasingly popular procedure, and contradict published results regarding the relationship between stem length and failure.

A consecutive series of one hundred and thirty-one THA revisions using a cemented femoral component were reviewed. Ninety-four hips in eighty-five patients alive > six years post-operatively were studied with a mean follow-up of 10.5 years. Hips excluded from analysis were thirty deceased and seven lost to follow-up before six years post-operatively. Implant success was graded radiographically and by comparing pre-operative to recent Harris Hip scores.

Of the ninety-four hips, fifteen (16%) femoral components were subsequently revised; nine (9.6%) for aseptic loosening, three (3.2%) for periprosthetic fracture, and one (1.1%) for each of stem fracture, instability, and sepsis. Survival at 10.5 years was 86.9% for all reasons and 91.0% for aseptic loosening as an endpoint. 76.9% of the retained components were radiologically classified as stable or possibly loose at follow-up. Factors significant for failure included age at revision < sixty years (p = 0.003), male patients (p = 0.036) and stems > 200 mm in length (p = 0.024).

The timing of liner exchange for retroacetabular oste-olysis in THA remains uncertain. Liner exchange should be done before the shell becomes loose. The purpose of this study was to determine the radiographic quantity of osteolysis that will predict impending loosening of the cementless shell. Osteolytic lesions were quantified radiographically using three different measures. Implant stability was confirmed intraoperatively. Percent of shell circumference with surrounding osteolysis appears to be more predictive of cementless shell loosening than the area of osteolysis. When greater than fifty percent of the shell circumference has osteolysis on AP or lateral films, liner exchange is necessary.

The timing of liner exchange for retroacetabular osteolysis in cementless THA remains uncertain. Liner exchange should be done before the shell becomes loose.

To determine the radiographic quantity of osteolysis that will predict impending loosening of the cementless shell.

Osteolytic areas differ between loose and stable shells.

Between 1992 to 2002, seventy-one cementless shells of the same design were revised at our institution; forty-six were for aseptic retroacetabular osteolysis. Radiographs and a computer-assisted technique were used to quantify osteolytic areas and percent of shell circumference associated with lesions. Implant stability was confirmed intraoperatively.

Of twenty-six stable and twenty loose shells, the average area of osteolysis on AP radiographs showed no significant difference (Stable 591mm², Loose 630 mm², p greater than 0.05); whereas, lateral radiographs demonstrated a significant difference (Stable 546 mm², Loose 837 mm², p 0.05). The percentage of shell circumference with associated osteolysis on AP and lateral films demonstrated a significant difference (AP: Stable 60, Loose 75, p 0.042; LATERAL: Stable 49, Loose73, p 0.016). Diagnostic criteria of fifty percent shell circumference associated with osteolysis on AP films has sensitivity 1, specificity 0.27 while the same criteria on lateral films has sensitivity 0.84, specificity 0.54 for shell loosening.

Percent of shell circumference with surrounding oste-olysis appears to be more predictive of cementless shell loosening than the area of osteolysis. When greater than fifty percent of the shell circumference has osteolysis on AP or lateral films, liner exchange is necessary.

Intramedullary tibial nailing was performed in ten paired cadavers and the insertion of a medial-to-lateral proximal oblique locking screw was simulated in each specimen. Anatomical dissection was undertaken to determine the relationship of the common peroneal nerve to the cross-screw.

The common peroneal nerve was contacted directly in four tibiae and the cross-screw was a mean of 2.6 mm (1.0 to 10.7) away from the nerve in the remaining 16. Iatrogenic injury to the common peroneal nerve by medial-to-lateral proximal oblique locking screws is therefore a significant risk during tibial nailing.

Introduction and Aims: Cemented femoral revision total hip arthroplasty has been associated with early mechanical failure by aseptic loosening. This study was performed to determine the long-term survival of cemented femoral revision arthroplasty and to identify factors predictive of failure.

Method: One hundred and twenty-nine cemented femoral revision cases were reviewed to determine component survival. Ninety-seven hips with a minimum follow-up of five years were included for survival analysis and tests of significance. Harris hip scores were used to quantify clinical outcomes. Complete radiographic series were reviewed. Kaplan-Meier survival curves were calculated. Clinical and surgical factors were analysed to determine if they were predictive of failure.

Results: Individual Harris hip scores improved to a mean of 71 at the most recent follow-up from a mean pre-operative score of 52 (p< 0.001). Kaplan-Meier survival at 10 years was 91%, with revision for aseptic loosening of the femoral component as the endpoint and 71% with mechanical failure as the endpoint. Patients older than 60 years experienced greater long-term component survival and less pain than patients younger than sixty years (p< 0.05). Good quality post-operative cement mantles were associated with better long-term radiographic fixation (p< 0.001). Poor femoral bone quality was significantly associated with an increased rate of re-revision for aseptic loosening (p=0.021).

Conclusion: Revision femoral THA with cement remains an option in selected patients with acceptable 10-year survival and fair radiographic fixation. Patients demonstrated acceptable clinical outcomes at 10 years and few experienced significant pain. The best results may be achieved in older patients with adequate bone stock and modern cementing techniques.

Introduction and Aims: Problem: The timing of liner exchange for retroacetabular osteolysis in THA remains uncertain. Liner exchange should be done before the shell becomes loose.

Purpose: To determine the radiographic quantity of osteolysis that will predict impending loosening of the cementless shell.

Hypothesis: Osteolytic areas differ between loose and stable shells.

Method: Between 1992 and 2002, 71 cementless shells of the same design were revised at our institution; 46 were for aseptic retroacetabular osteolysis. Radiographs and a computer-assisted technique were used to quantify osteolytic areas and percent of shell circumference associated with lesions. Implant stability was confirmed intra-operatively.

Results: Of 26 stable and 20 loose shells, the average area of osteolysis on AP radiographs showed no significant difference (Stable 591mm2, Loose 630 mm2, p greater than 0.05); whereas, lateral radiographs demonstrated a significant difference (Stable 546 mm2, Loose 837 mm2, p 0.05). The percentage of shell circumference with associated osteolysis on AP and lateral films demonstrated a significant difference (AP: Stable 60, Loose 75, p 0.042; LATERAL: Stable 49, Loose 73, p 0.016). Diagnostic criteria of 50 percent shell circumference associated with osteolysis on AP films has sensitivity 1.0, specificity 0.27, while the same criteria on lateral films has sensitivity 0.84, specificity 0.54 for shell loosening.

Conclusion: Percent of shell circumference with surrounding osteolysis appears to be more predictive of cementless shell loosening than the area of osteolysis. When greater than 50 percent of the shell circumference has osteolysis on AP or lateral films, liner exchange is necessary.

Introduction and Aims: Problem: Patellar resurfacing in TKA remains controversial. Purpose: To evaluate the results of resurfacing/non-resurfacing of the patella in a randomised controlled clinical trial at a minimum of 10 years of follow-up.

Method: One hundred knees (90 patients) with osteoarthritis were enrolled in a prospective randomised controlled double-blinded trial using the same posterior cruciate retaining total knee replacement. Patients were randomised to resurfacing or non-resurfacing of the patella. Evaluations were performed pre-operatively and yearly to a minimum of 10 years (range 10.1–11.5 years) postoperatively. Disease-specific (Knee Society Clinical Rating System), functional (stair climbing, knee flexion/extension torques, patellar examination) outcomes were measured. Patient satisfaction, anterior knee pain, and patellofemoral questionnaires were completed. Intra-operative grading of the articular cartilage was performed.

Results: No patients were lost to follow-up; 46 knees remained alive. Nine revisions (9/90–10%) were performed – 7/48 (15%) in the non-resurfaced and 2/42 (5%) in the resurfaced group. Three knees in the non-resurfaced group were revised to a resurfaced patella for anterior knee pain. One resurfaced patella was complicated by AVN and fracture, requiring revision. No significant difference was found between the groups regarding revision rates, KSCR score, functional, satisfaction, anterior knee pain, patellofemoral, and radiographic outcomes. Intraoperative cartilage quality was not a predictor of outcome.

Conclusions: This study represents the longest follow-up to date of a randomised controlled clinical trial to examine patellar resurfacing in TKA. The results showed no significant difference between the groups for all outcome measures at a minimum of 10 years.