We aimed to determine whether proximal femoral bone remodelling, as measured by DEXA scan for each Gruen Zone, differed for 3 different femoral stem designs. These were:
Group 1 – Triple taper polished (C-stem J&
J DePuy) Group 2 – Double taper polished (TPS J&
J DePuy) Group 3 – Collared satin finish stem (Stanmore Biomet) Ethical Committee approval was obtained and all patients gave informed consent. All operations were performed by 3 surgeons using a standard lateral approach, third generation cementing technique and a standard post-operative regime. Seventy-five patients were randomised prospectively using a stratified randomisation programme for known risk factors in bone density. The randomisation was stratified by age, sex, Charnley Group (A or B), BMI and femoral neck bone mineral density. There were 25 patients in each Group, 5 patients did not have complete data sets and were therefore withdrawn from evaluation. The Groups were similar with regard to age, sex, BMI, BMD and Charnley Group. Patients were followed up at 3, 6, 12 and 24 months by Nurse Practitioners for clinical and radiological evaluation and DEXA scan at each time of follow-up. There were no catastrophic failures of sepsis or dislocation. All patients functioned well at 24 months by Harris Hip Score. The bone remodelling pattern will be described for each stem design. Findings are summarised thus. In the lateral Gruen Zones the triple taper and collared stem design faired better and both behaved differently to the double taper design. In Gruen Zone 7, all stems demonstrated reduced bone density as compared to pre-operative scans but this was less with the triple taper design.
We report the clinical and radiographic outcome of a consecutive series of 219 hydroxyapatite-coated total knee replacements with a follow-up of 5 to 8 years. Patients who fulfilled the entry criteria were included in a prospective study from early 1997 to late 1999. Regular clinical &
functional assessment was subsequently performed using the Knee Society Score, WOMAC &
SF-12 self-assessment questionnaires. Analysis of fluoroscopically controlled radiographs was performed using the American Knee Society Score. All living patients (186 knees) were followed-up. Exhaustive efforts were made to ensure that no patient was lost to follow-up. 28 patients (30 knees) were deceased. There have been 3 revisions. The mean pre-operative Knee Score of 43.8 increased to 77.1 and the mean pre-operative Function Score of 20.3 increased to 63.4 at 5 years. The WOMAC scores also showed marked improvement from pre-operative status after 5 years minimum follow-up: pain 250 pre-op to 157, stiffness 115 pre-op to 56 and function 910 pre-op to 588. There was no radiographic evidence of loosening or migration. The average American Knee Society Score for each component was 4. Small gaps between the bone-implant interface were observed to heal over the first year. A separate phenomenon of focal osteopenia is also described in a small number of well-fixed femoral components (12 of 219). To date, 3 prostheses have been revised, 2 due to deep infection and 1 due to tibial tray subsidence. A survivor-ship of 98.6% has been achieved at 8 years. We believe this to be the first medium term study for the Duracon HA coated knee arthroplasty system, showing excellent clinical and radiographic outcome, with 100% follow-up at 5 to 8 years.
We retrospectively reviewed 19 femoral non-unions. Age group ranged from 17–72 yrs with mean of 40 yrs. 12 were men and 7 were women. 11 fractures involved diaphysis and 8 involved supracondylar area. 5 cases were infected non-unions. Time from fracture to defini-tive treatment varied from 5 to 88 months (mean 21 months). Open technique was used in 18 cases. In 8 cases we have used autogenous cancellous bone graft and in 3 cases BMP7 was used in addition to bone graft. 9 cases were treated with Ilizarov frame without bone graft, 6 with plate &
bone graft, 3 with intramedullary nail and 1 with bone graft alone. Internal bone transport was carried out in 5 cases to achieve limb length equality. Fracture union was achieved in 16 patients with 7 excellent and 8 good results as per ASAMI criteria. 15 cases achieved excellent to good functional results. Because of persistent infection, 2 distal femoral non-unions required transfemoral amputation. Treatment was discontinued due to psychiatric illness in 1 patient with Ilizarov frame. Two of the patients in Supracondylar group developed knee stiffness. Pin tract infection is a common complication in Ilizarov group. Adequate reduction &
stabilization is key to success. Non-unions without any complications can be treated with exchange nail or open reduction and plating. Ilizarov method is effective for non-unions complicated by distal location, infection and bone loss. Psychological assessment is important before considering Ilizarov method of treatment.
Open technique was used in 18 cases. In 8 cases we have used autogenous cancellous bone graft and in 3 cases BMP7 was used in addition to bone graft. 9 cases were treated with Ilizarov frame without bone graft, 6 with plate and bone graft, 3 with intramedullary nail and 1 with bone graft alone. Internal bone transport was carried out in 5 cases to achieve limb length equality. Fracture union was achieved in 16 patients with 7 excellent and 8 good results as per ASAMI criteria. 15 cases achieved excellent to good functional results. Because of persistent infection, 2 distal femoral non-unions required transfemoral amputation. Treatment was discontinued due to psychiatric illness in 1 patient with Ilizarov frame. Two of the patients in supracondylar group developed knee stiffness. Pin tract infection is a common complication in Ilizarov group.