Femoral stem design affects periprosthetic bone mineral density (BMD), which may impact long term survival of cementless implants in total hip arthroplasty (THA). The aim of this study was to examine proximal femoral BMD in three morphologically different uncemented femoral stems designs to investigate whether one particular design resulted in improved preservation of BMD. 119 patients were randomized to receive either a proximally coated dual taper wedge stem, a proximally coated anatomic stem or a fully coated collarless triple tapered stem. Dual energy x-ray absorptiometry scans (Lunar iDXA, GE Healthcare, Madison, WI) assessed BMD across the seven Gruen zones pre-operatively, and post-operatively at 6-weeks, 1-year, and 2-years comparing the unoperated contralateral femur as a control. BMD increased in zones one (2.5%), two (17.1%), three (13.0%), five (10%) and six (17.9%) for all stems. Greater preservation of BMD was measured on the lateral cortex (zone 2) for both the dual taper wedge and anatomic stems (p = 0.019). The dual taper wedge stem also demonstrated preservation of BMD in the medial calcar (zone 7) whilst the anatomic and triple taper stem declined in this region, however this was not statistically significant (p = 0.059). BMD decreased on average by 2.1% in the mid-diaphysis region, distal to the stem tip (zone 4) for all implants. All stems performed equivalently at final follow-up in all patient reported outcome measures. Implant design was shown to impact BMD changes. All stems preserved bone at the metaphyseal level in early follow-up, which theoretically indicates favorable implant fixation. There was no significant stress shielding observed, however longer follow-up is required to elucidate the impact of this finding on implant survivorship.
PFFs are an increasing burden presenting to the acute trauma services. The purpose of this study is to show that cemented revision for Vancouver B2/B3 PFFs is a safe option in the geriatric population, allows early pain-free weight bearing and comparable to a control-group of uncemented stems with regard to return to theatre and revision surgery. A retrospective review was conducted of all PFFs treated in a Level 1 trauma centre from 2015-2020. Follow up x-rays and clinical course through electronic chart was reviewed for 78 cemented revisions and 49 uncemented revisions for PFF. Primary endpoints were all cause revision and return to theatre for any reason. Secondary endpoints recorded mobility status and all-cause mortality. In the cemented group there were 73 Vancouver B2, 5 Vancouver B3 PFF; the mean age was 79.7 years and mean radiological follow-up of 11.9 months. In the cementless group there were 32 Vancouver B2 and 17 Vancouver B3 PFFs; with all 49 patients undergoing distally bearing uncemented revision, the mean age was 72.7 years and mean radiological follow-up of 21.3 months. Patients treated with a cemented prosthesis had significantly higher ASA score (2.94 -v- 2.43, p<0.001). The primary endpoints showed that there was no significant difference in all cause revision 3/78 and 5/49 p=0.077, or return to theatre 13/78 -v- 12/49 p=0.142. Secondary endpoints revealed no significant difference in in-hospital mortality. The cementless group were more likely to be mobilising without any aid at latest follow-up 35/49 -v- 24/78 p<0.001. The use of cemented revision femoral component in the setting of PFFs is one option in the algorithm for management of unstable PFFs according to the Vancouver classification. Evidence from this case-control study, shows that the all-cause revision and return to theatre for any cause was comparable in both groups.
Femoral stem design affects periprosthetic bone mineral density (BMD), which may impact long term survival of cementless implants in total hip arthroplasty (THA). The aim of this study was to examine proximal femoral BMD in three morphologically different uncemented femoral stems designs to investigate whether one particular design resulted in improved preservation of BMDMethods: 119 patients were randomised to receive either a proximally coated dual taper wedge stem, a proximally coated anatomic stem or a fully coated collarless triple tapered stem. All surgeries were performed via the posterior approach with mobilization on the day of surgery. Dual energy x-ray absorptiometry scans (Lunar iDXA, GE Healthcare, Madison, WI) assessed BMD across the seven Gruen zones pre-operatively, and post-operatively at 6-weeks, 1-year, and 2-years and compared to the unoperated contralateral femur as a control. Patient reported outcome measures of pain, function and health were also included at these corresponding follow-ups. BMD increased in zones one (2.5%), two (17.1%), three (13.0%), five (10%) and six (17.9%) for all stems. Greater preservation of BMD was measured on the lateral cortex (zone 2) for both the dual taper wedge and anatomic stems (p = 0.019). The dual taper wedge stem also demonstrated preservation of BMD in the medial calcar (zone 7) whilst the anatomic and triple taper stem declined in this region, however this was not statistically significant (p = 0.059). BMD decreased on average by 2.1% inthe mid-diaphysis region, distal to the stem tip (zone 4) for all implants. All stems performed equivalently at final follow-up in all patient reported outcome measures. This study demonstrated maintenance of femoral BMD in three different cementless femoral stem designs, with all achieving excellent improvements in patient reported outcomes. There was no significant stress shielding observed, however longer follow-up is required to elucidate the impact of this finding on implant survivorship.
Uncemented femoral components of hip arthroplasty are believed to have a higher risk of subsidence in older patient groups. This has not been conclusively related to a poorer outcome of the arthroplasty over time. Our aim is to measure prevalence of subsidence in uncemented femoral components in a population of patients over 75 years of age and correlate with clinical outcome measures. Patients over 75 years of age from Jan 2002 to Aug 2009 had uncemented THJR at the discretion of the senior surgeon (RF). Pre-operative Charnley Hip Classification and Harris Hip Scores were recorded, as were HHS at 6 weeks and 1 year post-operatively for all patients. Post-operative radiographs were retrospectively reviewed and presence of subsidence quantified at 1 year and subsequent follow-ups. 83 patients had 92 uncemented THJR in the designated time frame. 5 pts were lost to follow-up or died within 12 months after operation leaving 78 patients and 87 hips for assessment. Average pre-op HHS 40.6 (13.1–64.6) and Charnley Classification noted (A 55.4 %: B 30.4%: C 14.1%). 12/87 (13.8%) hips had subsidence > 2mm (2 – 18mm) noted at 1 year radiographs. Average HHS for those with >2mm subsidence was 89.4 (69.7–100; median 93.9) compared to 90.7 (64.7 – 100; median 91.9) for those with < 2mm subsidence. 4 patients underwent revision procedures during follow-up period, all for periprosthetic fracture following falls. In appropriately selected patients over 75 years of age, the presence of subsidence in uncemented femoral components does not seem to result in poorer outcome measures.
The purpose of this study was to evaluate the results of LISS fixation of distal femur fractures This is a single-centre review of 64 consecutive LISS plates used for distal femoral fractures over 5.5 years. No patients were excluded and all were followed for a minimum of one year (mean 37 months). Primary outcomes were time to union, knee ROM, Knee Outcome Survey Activities of Daily Living Scale and SF-36 scores. Secondary outcomes were fracture alignment, additional surgery and complications. Sixty-four fractures were followed in 62 patients with a bimodal distribution of age (mean 66 yrs, 14–98 years). Two major subgroups were young patients (55 and under) with high-energy fractures, most common in men (12:4) and elderly patients with insufficiency or peri-prosthetic fractures, more common in women (11:35). Twenty-two patients died prior to clinical follow-up in the study, but only eight of these died prior to radiological and clinical bony union. No other patients were lost to follow-up. Ninety-four percent of patients achieved within 10 degrees of full knee extension (mean 1.4 degrees), whilst 74% achieved knee flexion >
100 degrees and all achieved 90 degrees. Mean union time was 6.8 months and there was one infected non-union. There were 28 re-operations in 17 patients. Ten were for removal of metal-ware, four required bone grafting and two had revision of fixation. LISS fixation is a reproducible technique, producing reliable union, low re-operation rates (other than metal-ware removal) and good restoration of knee function. LISS is good for both high and low energy injury patterns and works well in the presence of both knee and hip replacements. We recommend bi-cortical proximal fixation in osteoporotic bone.
