The Oxford hip score (OHS) is a 12-item questionnaire designed
and developed to assess function and pain from the perspective of
patients who are undergoing total hip replacement (THR). The OHS
has been shown to be consistent, reliable, valid and sensitive to
clinical change following THR. It has been translated into different
languages, but no adequately translated, adapted and validated Danish
language version exists. The OHS was translated and cross-culturally adapted into Danish
from the original English version, using methods based on best-practice
guidelines. The translation was tested for psychometric quality
in patients drawn from a cohort from the Danish Hip Arthroplasty
Register (DHR).Objectives
Methods
For bone grafting procedures, the use of autologous bone is considered the gold standard, as it is has a better healing capacity compared to other alternatives as allograft and synthetic bone substitutes. However, as there are several drawbacks related to autografting (infection, nerve- or vascular damage, chronic pain problems, abdominal herniation), there has been a targeted effort to improve the healing capacities of synthetic bone substitutes. To evaluate the performance of a carbonated osteoionductive hydroxyapatite (CHA) scaffold of clinical relevant size (Ø=15mm, H=50mm) in a sheep model of multi level posterolateral intertransverse lumbar spine fusion after activation with autologous bone marrow nuclear cells (BMNC) in a flow perfusion bioreactor.Background
Aim
9,596 of the 280,201 primary THRs, had been revised. Ten-years survival was 91.9% (95% CI: 91.5 – 92.3) in Denmark, 93.9% (95% CI: 93.6–94.1) in Sweden, and 92.6% (95% CI: 92.3–93.0) in Norway. In Sweden and Norway 23% of revisions were due to dislocation, compared to 34% in Denmark. Replacement of only cup or liner constituted 29% of the revisions in Sweden, 33% in Norway, and 44% in Denmark.
There were no significant differences between the two approaches with regard to pre- and post-operative HHS, WOMAC, patient satisfaction, level of activity and EQ5D
At follow-up weight-bearing AP pelvis radiographs were obtained. OA was present when the minimum joint space width was <
2.0 mm. Radiographs of sex- and age-matched controls were obtained from The Copenhagen City Heart Study. The following criteria for exclusion were applied:
insufficient or missing radiographs patients who refused to participate, emigrated persons, persons lost to follow-up, patients with previous surgery to pelvis or lower limbs and dead persons. 52 patients (55 hips) were enrolled in the study and 115 patients (136 hips) were excluded. Mean age for men at follow-up was 53 years and for women 55 years.
This study also raised some methodological questions that this study tries to answer. What is happening in the dead space around the catheter in the drill canal? And is there an equilibrium period after the insertion of the catheter.
Ex vivo study: in 5 syringes with 5 ml human blood a microdialysis catheter was inserted and microdialysis performed over 3 hours. In vivo study: in the proximal part of the femur in 6 mature Göttingen mini pigs a drill hole was made and microdialysis was performed over 3 hours. The pigs were kept normoventilated during the experiment.
Ex vivo: the microdialysis results showed that lactate kept a steady level and glucose and glycerol all fell, pyruvate fell but leveled out. The lactate/pyruvate ratio increased from 13(4) to 32(6) (p<
0.001). In vivo: relative recovery was 57(11)%. Lactate increased, pyruvate stayed constant, glucose and glycerol fell. The lactate/pyruvate ratio increased from initial 30(8) to 37(8) after 1 hour (p=0.007) but no significant change from 1 to 2 hours was observed.
The in vivo study indicates that an equilibrium period is necessary or that a reference measurement in healthy bone must be used when performing short measurements in bone.
We compared patients’ characteristics and outcome following THA in private and public hos-pitals.
To detect eventual difference in patient characteristics- age, gender, diagnosis leading to THA, Carlson’s comorbidity score and Charnley category were evaluated. We matched 3 658 cases operated in private with 3 658 controllers operated in public hospitals on propensity score. Scoring parameters were age, gender, diagnosis leading to THA, Carlson’s comorbidity score, Charnley category, operating time, type of anesthesia and type of prosthesis. We used multivariate logistic regression on propensity score matched data to assess association between type of hospital and outcome by computing relative risks and 95% Confidence Interval (CI). Outcomes were perioperative complications, readmission within 3 months, re-operation within 2 years, implant failure after 5 years, and mortality within 3 months of surgery.
Patients in private and propensity matched controls from public hospitals showed no differences in age, gender, diagnosis leading to THA, Carlson’s comorbidity score, Charnley category, operating time, type of anesthesia and type of prosthesis (p-value <
0,0001). Based on matched data, private hospitals had lower relative risk for perioperative complications (0.39, 0.26–0.60), reoperations (0.59, 0.41–0.83) and readmissions (0.57, 0.42–0.77) compared with public. There was no difference in mortality or implant failure.
We found significant difference between patient characteristics operated at public versus private hospitals. No difference was evident regarding mortality and implant failure but for complications, reoperations and readmissions between private and public hospitals.
Radiographs of sex- and age-matched controls for the follow-up group were obtained from The Copenhagen City Heart Study. The following criteria for exclusion were applied
emigrated persons, persons lost to follow-up and patients with previous surgery to pelvis or lower limbs. 135 patients (156 hips) were enrolled in this study and 32 patients (35 hips) were excluded.
Surgery and postoperative regime were identical in the two groups. CR-migration during cementation and stem insertion was calculated and the quality of cementation was evaluated on the post-operative X-ray according to the criteria by Barrack et Al( Mean values are presented with 95% CI. An unpaired T-test was used to analyse the differences in CR migration and the quality of cementation quality.
Regarding quality of cementation the mean value in the Imset group were 2.8 which was significantly better in the Hardinge group=2.1 (P=0.003)
Resurfacing THA is claimed to transfer stress naturally to the femur neck and preserve proximal femoral bone mass postoperatively. DXA is an established method in estimating BMD around a standard THA, but due to the anteversion of the femur neck, rotation could affect the size of the neck-regions and thereby the BMD measurements around a RTHA. To our knowledge, this is the first study to analyze the effects of hip rotation on BMD in the femoral neck around a RTHA. We scanned the femoral neck of 15 patients twice in each position of 15° inward, 0° and 15° outward rotation, and analyzed BMD in a single and a six-region model. CVs were calculated for BMD in the same position as well as between different positions. For double measurements in the same position we found mean CVs of 3.1% (range 2.5% – 3.7%) and 4.6% (range 2.2% – 8.6%) in the one- and six-region models, respectively. When the 15° outward position was excluded, the CVs decreased to 2.8% and 4.0%. With rotation, the mean CVs rose to 5.4% (range 3.2%–7.2%) and 11.8% (range 2.7% – 36.3%). This effect was most pronounced in the 6-region model, predominantly in the lateral and distal parts of the femoral neck, where the change was significantly different from the fixated position. For the single-region model 15° rotation could be allowed without compromising the precision. We conclude that rotation adversely affects the precision of BMD measurements around a RTHA, but in the single-region model smaller rotations can be allowed. With the hip fixated the six-region model produces low CVs, acceptable for longitudinal studies. For maximal topographical detail we prefer the six-region model and recommend that future longitudinal DXA studies, including RTHA, be performed standardised, Preferably, with the hip in the neutral or internal rotation.
There is a great need for suitable large animal models that closely resemble osteoporosis in humans, and that they have adequate bone size for bone prosthesis and biomaterial research. This study aimed to investigate effects of a 7 month glucocorticoid (GC) treatment alone without ovariectomy on the properties of sheep cancellous bone. Eighteen female sheep were randomly allocated into 3 groups: group 1 (GC-1) received GC (0.60mg/kg/day methylprednisolone) 5 days weekly for 7 months; group 2 (GC-2) received the same treatment regime for 7 months, and further observed for 3 months without GC; and group 3 served as the control group, and left untreated for 7 months. The sheep received restricted diet. After 7 months of GC treatment. Cancellous bone volume fraction of the 5th lumbar vertebra in the GC-1 group was reduced by −35%, trabecular thickness by −28%, and changed from typical plate structure to a combination of plate and rod structure with increased connectivity by 202%. Bone strength was reduced by 52%. Bone formation marker, serum osteocalcin of GC-1, was reduced by 71% at 7 months, but recovered with an increase of 45% at 10 month in the GC-2 group. Similar trends were also seen in the femur and tibia. At 10 months, the GC-2 group had microarchitectural and mechanical properties similar to the level of the control sheep. We have demonstrated in this study that 7 month high-dose GC on bone density and microarchitecture are comparable with those observed in human after long-term GC treatment. Moreover, we have shown that the bone quality with regard to strength and microarchitecture recovers after 3 months further observation without GC. This suggests that a prolonged administration of GC is needed for long-term observation to keep osteopenic bone. The model will be useful in pre-clinical studies.
The procedures were reviewed with primary focus on perioperative blood loss, length of surgery and neurovascular complications. Patients who underwent combined surgery of acetabulum and femur were excluded. Data are presented as mean with 95% confidence interval (CI) in brackets.
The MI group had 1 case of major arterial bleeding, however no blood transfusion. The II group had 2 cases of arterial thrombosis and one transient sciatic nerve palsy. One patient received blood transfusion.