We present minimum 20 year results of a randomized, prospective double blinded trial (RCT) of cross-linked versus conventional polyethylene (PE), using a computer assisted method of PE wear measurement.

After Ethics Committee approval, 122 patients were enrolled into an RCT comparing Enduron (non cross-linked PE) and highly cross-linked Marathon PE (DePuy, Leeds, UK). Other than the PE liners, identical components were used, a Duraloc 300 metal shell with one screw, a 28mm CoCr femoral head and a cemented Charnley Elite femoral stem. All patients were followed with anteroposterior (A∼P) and lateral radiographs at 3 days, 6 weeks, 3 months, 6 months, 1, 2, 3, 4, 5, 10 and 20 years. PE wear was measured with PolyMig, which has a phantom validated accuracy of ± 0.09mm.

At minimum 20 year follow-up, 47 patients had died, 5 of which had been revised prior to their death. Another 32 patients were revised and alive, leaving 43 patients unrevised and alive (15 Enduron, 28 Marathon). No patients were lost to follow-up, but 2 were not able to be radiographed (dementia), leaving 41 patients (15 Enduron, 26 Marathon) available for PE wear measurement. After the bedding-in period, Enduron liners had a wear rate of 0.182 mm/year, and Marathon liners had a wear rate of 0.028 mm/year. At 20 years follow-up, 37 patients had required revision. Patients with conventional PE had three times the revision rate (28/37) of those who received XLPE (9/37).

This is the longest term RCT showing substantially improved clinical and radiological results when XLPE is used as the bearing surface.

This study examined the effect of seven vs. five day physiotherapy on hospital LOS for total joint replacement (TJR) patients. 1055 consecutive TJR patients were studied. Seven day PT significantly reduced LOS for TJR patients (0.73 days) and the subgroup of total hip replacement patients (0.80 days). Decreases in TJR LOS reduced hospital costs by $100,000. Older patients and patients with greater co-morbidities had a longer LOS with both five and seven day PT, but their LOS was less with seven day PT. This study provides strong evidence for providing seven day PT for TJR patients.

The purpose of this study was to determine the effect of five vs. seven day/week physiotherapy (PT) on acute care, length of stay (LOS) for TJR patients.

The inpatient discharge abstract database was used to retrospectively identify TJR patients who were admitted on January 1, 2000 or later and discharged by March 31, 2002 or earlier. Patients were excluded if they died in hospital or were discharged to another acute care facility. PT was enhanced from five to seven days/week on March 10, 2001. This date was used to divide patients into PRE and POST (enhanced PT) groups. Differences in LOS (PRE vs. POST) were analyzed for all TJR, and separately for THR (total hip replacement) and TKR (total knee replacement) patients, using t-tests. Potential interactions between group (PRE, POST) and age (young < 70 yrs, old ≥ 70 yrs), gender, and co-morbidity were analyzed with two-way ANOVA’s (group x other variable). LOS acute care savings were calculated using the unit-specific per diem cost.

1055 patients were studied. LOS was significantly reduced for TJR (0.73 days) and THR (0.80 days) patients. TJR decreases in LOS reduced acute care costs by $100,000. Age and co-morbidity had significant main effects but no interaction on LOS.

LOS and hospital costs were reduced for TJR patients with seven day PT. The fact that a decrease in LOS was seen in a large sample, in both young and old patients and patients with and without comorbidities, provides strong evidence to support seven day PT for TJR patients.