The aim of this study was to evaluate the diagnostic accuracy of the synovial alpha-defensin enzyme-linked immunosorbent assay (ELISA) for the diagnosis of prosthetic joint infection (PJI) in the work-up prior to revision of total hip (THA) and knee arthroplasty (TKA). Inclusion criteria for this prospective cohort study were acute or chronic symptoms of the index joint without specific exclusion criteria. Synovial fluid aspirates of 202 patients were analyzed and semiquantitative laboratory alpha-defensin ELISA was performed. Final diagnosis of PJI was established by examination of samples obtained during revision surgery.Aims
Patients and Methods
Several factors have been implicated in unsatisfactory
results after total hip replacement (THR). We examined whether femoral
offset, as measured on digitised post-operative radiographs, was
associated with pain after THR. The routine post-operative radiographs
of 362 patients (230 women and 132 men, mean age 70.0 years (35.2
to 90.5)) who received primary unilateral THRs of varying designs
were measured after calibration. The femoral offset was calculated
using the known dimensions of the implants to control for femoral
rotation. Femoral offset was categorised into three groups: normal
offset (within 5 mm of the height-adjusted femoral offset), low
offset and high offset. We determined the associations to the absolute
final score and the improvement in the mean Western Ontario and
McMaster Universities osteoarthritis index (WOMAC) pain subscale
scores at three, six, 12 and 24 months, adjusting for confounding
variables. The amount of femoral offset was associated with the mean WOMAC
pain subscale score at all points of follow-up, with the low-offset
group reporting less WOMAC pain than the normal or high-offset groups
(six months: 7.01 ( Cite this article:
We investigated whether an asymmetric extension
gap seen on routine post-operative radiographs after primary total
knee replacement (TKR) is associated with pain at three, six, 12
and 24 months’ follow-up. On radiographs of 277 patients after primary
TKR we measured the distance between the tibial tray and the femoral
condyle on both the medial and lateral sides. A difference was defined
as an asymmetric extension gap. We considered three groups (no asymmetric
gap, medial-opening and lateral-opening gap) and calculated the
associations with the Western Ontario and McMaster Universities
osteoarthritis index pain scores over time. Those with an asymmetric extension gap of ≥ 1.5 mm had a significant
association with pain scores at three months’ follow-up; patients
with a medial-opening extension gap reported more pain and patients
with a lateral-opening extension gap reported less pain (p = 0.036).
This effect was still significant at six months (p = 0.044), but had
lost significance by 12 months (p = 0.924). When adjusting for multiple
cofounders the improvement in pain was more pronounced in patients
with a lateral-opening extension gap than in those with a medial-opening extension
gap at three (p = 0.037) and six months’ (p = 0.027) follow-up. Cite this article:
Although the Western Ontario and McMaster Universities
(WOMAC) osteoarthritis index was originally developed for the assessment
of non-operative treatment, it is commonly used to evaluate patients
undergoing either total hip (THR) or total knee replacement (TKR).
We assessed the importance of the 17 WOMAC function items from the perspective
of 1198 patients who underwent either THR (n = 704) or TKR (n =
494) in order to develop joint-specific short forms. After these
patients were administered the WOMAC pre-operatively and at three,
six, 12 and 24 months’ follow-up, they were asked to nominate an
item of the function scale that was most important to them. The
items chosen were significantly different between patients undergoing
THR and those undergoing TKR (p <
0.001), and there was a shift
in the priorities after surgery in both groups. Setting a threshold
for prioritised items of ≥ 5% across all follow-up, eight items
were selected for THR and seven for TKR, of which six items were
common to both. The items comprising specific WOMAC-THR and TKR
function short forms were found to be equally responsive compared
with the original WOMAC function form. Cite this article:
Statistical analyses were performed using statistical software. Probability of Type I error was set to 5% (alpha=0.05).
Osteonecrosis was found in 81 (97.6%) hips revised after fracture (p<
.0001). The vertical size of avascular necrosis in hips after acute postnecrotic fracture (21.1mm±8.5) was bigger (p<
.0001) than in both chronic (7.3mm±7.3) and acute mechanic (0.9 mm±1.2) fractures. Even though 33 (66.0%) of 50 patients with acute postnecrotic fracture were men (p=.0237), no significant differences between males and females were found with respect to age of patients (p=.3445) or duration of prosthesis implantation (p=.1232).
The proposed classification may help to understand causes of periprosthetic fractures after hip resurfacing arthroplasty.
We developed a computer assisted total knee arthroplasty system to help the surgeon achieving more intra-operative accuracy.
The thrust plate prosthesis is an implantat with metaphyseal fixation at the proximal femur, which leaves the diaphyseal bone untouched. Therefore this implant preferably is employed in younger patients. It is dependent on a good bone quality in the proximal femur. Because bone quality is reduced in patients with polyarthritis, this kind of endoprosthesis may have a higher failer rate than conventional stemmed endoprostheses in these patients. Therefore in patients with polyarthritis even short- end midterm results of the thrust plate prosthesis should be analyzed.
47 thrust plate prostheses were implanted in 42 patients with polyarthritis (29 with rheumatoid arthritis, 6 with juvenile chronic arthritis and 7 patients with spondarthritis) and followed prospectively. The average age at the operation was 40. 8 ± 10. 7 years. Each patient was clinically and radiologically examined preoperative, 3 and 6 months after the operation and at the end of each postoperative year. The mean follow-up was 26. 1 ± 10. 7 months. The clinical findings were evaluated using the Harris-Hip-Score. Radiologically 8 different zones at the thrust plate prosthesis were analyzed for radiolucencies.
During the first year the Harris-Hip-Score rose continuously from the preoperative average of 42. 4 ± 6. 5 points to 78. 8 ± 10. 3 points 3 months postoperatively, 82. 3 ± 9. 8 points 6 months postoperatively, and 86. 8 ± 10. 1 points 1 year after the operation. The following examinations showed Harris-Hip-Scores at the same level. 5 patients (5 joints, 10. 6%) had to undergo a revision of the thrust plate prosthesis due to aseptic loosening in 3 cases and septic loosening in 2 cases. 6 prostheses (12. 6 %) showed radiolucencies, mostly below the thrust plate in zone 1 and 2. 2 of these prostheses were certainly radiologically loose which raised the failure rate to 7 of 47 (14. 8 %).
The thrust plate prosthesis improves function and pain in patients with polyarthritis to a satisfactory degree. Concerning the failure rate this type seems to yield slightly worse results than cementless stemmed endoprostheses in the same patient group. Due to the preservation of the diaphysial bone of the femur and the possibility of an unproblematic change to a stemmed endoprosthesis the thrust plate prosthesis keeps its indication in younger patients with polyarthritis.
Survivorship analysis was performed on 479 Link V-Type cementless threaded acetabular cups on 310 cases with inflammatory arthritis, 138 cases with osteoarthritis and 31 cases with dysplastic hip. The average follow-up was 8. 6 ± 3. 2 years. The same analysis was performed on a modified cup with a smaller primary coil (type ”Bad Bramstedt”). This analysis had a mean follow-up period of 4. 5 ± 0. 7 years in 110 cases, including 49 with inflammatory arthritis, 49 with osteoarthritis and 12 with dysplastic hip. In a second approach 264 Link V-cups with a mean follow-up period of 8. 2 ± 2. 7 years and 59 modified cups with a mean follow-up period of 4. 6 ± 0. 7 years were radiologically examined for radiolucent lines according to Delee and Charnley and cup migration with regard to the method of Nunn et al. The cumulative survival rate for the former Link V-Type acetabular cup was 94. 5% after 5 years, 88. 1% after 10 years and 71. 2% after 15 years. The ”Bad Bramstedt” cup showed a 5 year survivorship rate of 97. 9%. Migration greater than 3 mm or tilting of the cup greater than 5 degrees was seen in 73% of the former type and in 39% of the modified cup. Radiolucent lines greater than 2 mm and detectable in two zones appeared in 6. 4% of the former Link V-Type and in 1. 7% of the ”Bad Bramstedt” cup design. Significant influence on cup migration was found in primary implant positioning and time elapsed. Due to the high rates of migration of the two implant designs and the frequent late aseptic loosening of the former Link V-Type acetabular component these two types of threaded cups were abandoned in favor of cementless press-fit cups.
Synovectomy in children with juvenile rheumatoid arthritis (JRA) and psoriatic arthritis (PSA) is still subject of controversial discussion. Our results of arthroscopic synovectomy of the knee in children with chronic inflammatory joint disease are presented.
From 1989–1997 27 synovectomies were performed in 27 children with inflammatory arthritis (15 JRA, 12 PSA). Average age at surgery was 12. 5 y (2. 9–17. 8 y). Mean follow-up was 4. 9 years.
Onset of disease and conservative therapy was documented. Each patient was physically and radiologically examined preoperatively and 24 children postoperatively (mean follow-up 4. 9 years). For arthroscopic shaver-assisted synovectomy of the knee we used minimum 4 portals and normally 6 portals (2 anterior, 2 suprapatellar and 2 posterior portals). In addition to the physical examination we used a special clinical score (Laurin 1974). We compared the pre- and postoperative limits of active and passive knee movement. We performed sonographs and radiographs of the infected joint. Radiography was classified following the Larsen-Scale. Patient and parents gave their opinion whether the operation was successful. Before surgery all children had intensive drug and physical therapy for 8–62 months (42 month). In the course of conservative treatment, knees had local joint treatment with triamcinolonhex-acetomid (THA), normally for three times before surgery. Preoperative X-rays showed Larsen stage I in 3 knee joints and Larsen stage 0 in the other knees.
In 85% of the children, we found good or excellent surgical outcome. 2 joints achieved fair and 2 joints poor outcome. Concerning subjective outcome 22 (82%) children had been very satisfied (56%) or satisfied (26%). 25 of the children’s parents would agree in the same surgical procedure again. In 6 knee joints we found recurrent synovitis. 2 of these knee joints were reoperated (30 and 22 month postoperatively with satisfying result), the other 4 joints were treated with THA i. a.. The 2 reoperations were regarded as poor result. We had no postoperative complications and the normal hospitalisation was 15 days. Prior to surgery, 12 knee joints had an average deficit of active knee extension of 10° (5–20°). Postoperatively, no extension deficit was found anymore in 25 of the knees. Compared to the contralateral knees, a flexion deficit of 10° (5–15°) was obtained postoperatively. At sonography, no joint effusion could be revealed. Postoperative X-rays showed no progression in Larsen stage. Outcome in children with oligoarthritis was better than in those with polyarthritic disease.
Early arthroscopic synovectomy of the knee in children with chronic inflammatory joint disease is, in case of failure of conservative treatment, a useful method of treatment. We propose early synovectomy of the knee joint as an essential part of the treatment scheme for children with inflammatory joint disease.
The concept of a new developed cup arthroplasty (Durom-Cup) is the replacement of the destroyed joint surface with minimal bone resection. In cases of additional cuff arthropathy the cup can be placed in a more valgic position to articulate with the glenoid and the acromion. The aim of this prospective study was to evaluate the results of this surface replacement as a hemiarthroplasty in rheumatoid arthritis with and without cuff arthropathy.
35 Durom-Cups of 29 patients (23 woman, 6 men) with rheumatoid arthritis were evaluated preoperatively and every 3 months postoperatively. 7 of these shoulders additionally had cuff arthropathy. The average age was 61. 6 ± 11. 8 years and the average follow-up 33. 4 ± 11. 8 months. The Constant-Score and SAS-function-Score were used and the cups were examined radiologically.
In rheumatic shoulders without cuff arthropathy the Constant-Score increased from 20. 6 ± 9. 5 points preoperatively to 47. 1 ± 14. 8 points 3 months postoperatively, to 47. 4 ± 13. 7 points 6 months, and to 56. 3 ± 8. 8 points 9 months postoperatively. During further follow-up it increased slightly and was 59. 5 ± 10. 1 points 12 months, 61. 8 ± 11. 3 points 18 months and 64. 6 ± 14. 8 points 24 months postoperatively. In shoulders with cuff arthropathy the Constant-Score increased from 17. 6 ± 8. 2 points preoperatively to 45. 0 ± 6. 4 points 3 months postoperatively, to 45. 5 ± 8. 5 points 6 months, and to 51. 5 ± 838 points 9 months postoperatively. At this level the Constant-Score stayed during further follow-up and was 54. 1 ± 10. 5 points 12 months, 56. 3 ± 9. 8 points 18 months, and 56. 1 ± 11. 6 points 24 months postoperatively. No complication, component loosening, or changes of cup position were observed.
The results of the Durom-Cup are encouraging. In shoulders with additional cuff arthropathy the limited goal criteria were reached always. Therefore cup arthroplasty is a good alternative other kinds of shoulder endoprostheses in rheumatic shoulders with and without cuff arthropathy.
The aim of this study was to analyse the long-term results of a cementless conical threaded cup with elevated inlay-rim, without bone grafting in joint replacement of dysplastic compared to non-dysplastic hips, and concerning the survival rate and the rate of cup migration. Most techniques of joint replacement of dysplastic hips contain bone grafting with more or less large-scale procedures. Without bone grafting, medialisation of the cup is often necessary. The conical threaded Link-V cup has the opportunity of stabilising the joint by using a polyethylene inlay with an elevated rim so that implantation in high angles of flexion and anteversion is possible. This is a technically easy procedure in dysplastic hips, but higher rates of loosening and cup migration are possible. A cementless conical threaded cup (Link V) with elevated inlay-rim was followed in 36 dysplastic hips (DH) and 167 non-dysplastic osteoarthritic hips (OA) over a minimum follow-up of five years. Mean follow-up in DH-hips was 8.4 2.3 years and in OA-patients 8.6 3.2 years. Survival analysis was performed and cup migration was radiographically analysed using the method of Nunn et al. The 10-year survival rate of the cup was 87% in DHhips compared to 92% in OA-hips. Luxation occurred in three OA-joints and none in DH-hips. Radiological cup migration was seen in 75% of DH-hips and in 70% of OA-joints. A change of the angle of flexion (mostly decrease) of more than two degrees was found in 50% of DH-hips and in 72% of OA-joints. There was vertical migration of more than 2 mm in 75% of DH-hips and in 70% of OA-hips, and a horizontal migration of more than 2 mm in 45% of DH-joints and in 40% of OA-hips. A radiolucent line of minimum 2 mm was seen in one case of each group. Using a cementless threaded cup with elevated inlayrim is a practicable and technically easy procedure for treatment of destroyed dysplastic hips. Although cup migration is frequent in dysplastic and non-dysplastic hips, failure-rate is still acceptable but tends to be higher in dysplastic than in non-dysplastic hips.
We evaluated histologically samples of synovial tissue from the knees of 50 patients with rheumatoid arthritis (RA). The samples were taken during revision for aseptic loosening. The findings were compared with those in 64 knees with osteoarthritis (OA) and aseptic loosening and in 18 knees with RA without loosening. The last group had been revised because of failure of the inlay or the coupling system of a constrained prosthesis. All the patients had had a total ventral synovectomy before implantation of the primary prosthesis. In all three groups a foreign-body reaction and lymphocellular infiltration were seen in more than 80% of the tissue samples. Deposits of fibrin were observed in about one-third to one-half of the knees in all groups. Typical signs of the reactivation of RA such as rheumatoid necrosis and/or proliferation of synovial stromal cells were found in 26% of knees with RA and loosening, but not in those with OA and loosening and in those with RA without loosening. Our findings show that reactivation of rheumatoid synovitis occurs after total knee replacement and may be a cofactor in aseptic loosening in patients with RA.
Treatment with corticosteroids is a risk factor for non-traumatic avascular necrosis of the femoral head, but the pathological mechanism is poorly understood. Short-term treatment with high doses of methylprednisolone is used in severe neurotrauma and after kidney and heart transplantation. We investigated the effect of such treatment on the pattern of perfusion of the femoral head and of bone in general in the pig. We allocated 15 immature pigs to treatment with high-dose methylprednisolone (20 mg/kg per day intramuscularly for three days, followed by 10 mg/kg intramuscularly for a further 11 days) and 15 to a control group. Perfusion of the systematically subdivided femoral head, proximal femur, acetabulum, humerus, and soft tissues was determined by the microsphere technique. Blood flow in bone was severely reduced in the steroid-treated group. The reduction of flow affected all the segments and the entire epiphysis of the femoral head. No changes in flow were found in non-osseous tissue. Short-term treatment with high-dose methylprednisolone causes reduction of osseous blood flow which may be the pathogenetic factor in the early stage of steroid-induced osteonecrosis.