Effect of medial-lateral malpositioning of the femoral component in total knee arthroplasty on anterior knee pain at greater than 8 years of follow-up.

BACKGROUND: The trochlea is often medialized after total knee arthroplasty (TKA) resulting in abnormal patellar tracking, which may lead to anterior knee pain. However, due to the difference in shape of the natural trochlea and the patellar groove of the femoral component, a medialization of the femoral component of 5 mm results in an equal patellar position at 0-30° of flexion. We tested the hypothesis that more medialization of the trochlea results in a higher VAS pain score and lower Kujala anterior knee pain score at midterm follow-up. METHODS: During surgery a special instrument was used to measure the mediolateral position of the natural trochlea and the prosthetic groove in 61 patients between 2004 and 2005. Patient reported outcome measures were used to investigate the clinical results (NRS-pain, NRS-satisfaction, KOOS-PS and Kujala knee score). RESULTS: In total 40 patients were included. The mean follow-up was 8.8 years. A medialization of ≥5 mm resulted in a significantly lower NRS-pain (0.2 vs. 1.4; p=0.004) and higher NRS-satisfaction (9.6 vs. 8.2; p=0.045). Overall clinical results were good; KOOS-PS was 33.9 and Kujala knee score was 72.1. CONCLUSIONS: The present study showed that a more medial position may result in a better postoperative outcome, which can probably be explained by the non-physiological lateral orientation of the trochlear groove in TKA designs. LEVEL OF EVIDENCE: Level III.

Continuous femoral nerve block after total knee arthroplasty?

BACKGROUND: A continuous femoral nerve block is frequently used as an adjunct therapy after total knee arthroplasty (TKA). However, there is still debate on its benefits. METHODS: In this prospective, randomized study, patients received a basic analgesic regimen of paracetamol and dicloflenac for the first 48 h postoperatively. In addition, the study group received a continuous femoral nerve block. A morphine patient-controlled analgesia pump was also available as a rescue analgesic to all the patients. Patients' numeric rating scores for pain, the amount of morphine consumed and its side effects during the first 48 h were recorded. Knee flexion angles achieved during the first week were registered. Three months postoperatively, patients completed Western Ontario and McMaster Universities Osteoarthritis Index and Knee Society Score. RESULTS: The study group (n=27) had less pain (P=0.0016) during the first 48 h, was more satisfied with the analgesia (P<0.001) and used less morphine (P=0.007) compared with the control group (n=26). Fewer patients were nauseated, vomited or were drowsy in the study group (P=0.001). Also, the study group achieved better knee flexion in the first 6 days after surgery (P=0.001), with more patients reaching 90 degrees flexion than the control group. However, after 3 months, there were no significant functional differences between the groups. CONCLUSION: A continuous femoral nerve block leads to better analgesia, less morphine consumption and less morphine-related side effects after TKA. Early functional recovery is improved, resulting in more patients reaching 90 degrees knee flexion after 6 days. However, after 3 months, no significant functional benefits were found.

Survival of massive allografts in segmental oncological bone defect reconstructions.

Reconstructions of large segmental bone defects after resection of bone tumours with massive structural allografts have a high number of reported complications including fracture, infection and non-union. Our goal is to report the survival and complications of massive allografts in our patients. A total of 32 patients were evaluated for fracture, infection, non-union rate and survival of their massive allograft reconstructions. The average follow-up for this group was five years and three months. The total fracture rate was 13% with a total infection rate of 16%. We found a low union rate of 25%. The total survival of the allografts was 80.8% (+/- 18.7%) after five years. We found a five-year allograft survival of 80.8% which is comparable with other studies.

How to quantify knee function after total knee arthroplasty?

Total knee arthroplasty (TKA) is being undertaken in a younger population than before and as a result the functional demands on the knee are likely to be increasing. As a consequence, it is important to define quantitative functional knee tests that can monitor any increase. A valuable functional knee test has to be able to distinguish small differences (selectivity) and has to be independent of pain (content validity). In this study, patient-based questionnaires (WOMAC and Knee Society score) and performance-based tests (sit-to-stand movement, maximal isometric contraction and timed-up-and-go) were used to assess which of these tests are selective and valid to measure knee function. Tests were considered to be selective if they could discriminate between knee patients and healthy control subjects, and to have functional content validity if they were relatively independent of pain. Twenty-eight patients were measured 16 months after surgery and compared to a healthy control group of 31 subjects. The sit-to-stand movement and timed-up-and-go test were both selective and functionally content valid. The timed-up-and-go test can be used for a quick initial assessment of global function and the sit-to-stand movement as a more biomechanical instrument identifying how the knee function of the patient is affected.

Functional evaluation of the TKA patient using the coordination and variability of rising.

A kinematic analysis of the knee function is important for the evaluation of total knee arthroplasties (TKA). We used the coordination and variability of rising from a chair as functional knee parameters. Twelve knee patients were measured prior to surgery (=pre-TKA group) and one year after surgery (=post-TKA group). A group of 15 healthy, age-matched subjects was selected as control group. The WOMAC questionnaire, frequently used by orthopaedic surgeons, was administered prior to the test. The test consisted of 10 times rising from a low chair and 10 times from a high chair. Knee and hip angles and angular velocities were measured with electrogoniometers. The relative phase (=MRP) between hip and knee was a measure for the coordination of rising and the standard deviation of the relative phase of the 10 trials (=SRP) was a measure for the variability. The coordination and variability of rising of the TKA patients were compared to the control group, and the relationship with the WOMAC questionnaire was calculated. The coordination of rising from a high chair and the variability of rising from both chair heights were significantly different for the pre-TKA group compared to the control group (p<0.05). The post-TKA group showed no significant differences with the control group, which indicates a functional recovery after TKA implantation. The functional parameters correlated adequately with the subjective WOMAC questionnaire. This study showed that our method is an objective measure of functionality and it will be worthwhile to use it as an additional evaluation tool.

The feasibility of total ankle prosthesis for severe arthropathy in haemophilia and prothrombin deficiency.

The standard treatment for end-stage arthropathy of the ankle joint in haemophilia has been fusion of the ankle joint. Total ankle replacement is used in osteoarthritis and especially in rheumatoid arthritis with good medium-term results. In this case series three patients are being described, in which a total of five total ankle replacements have been preformed. After a median follow up of 4.3 years (range 1-8.7) all prostheses were still in place and did not show any signs of loosening. Clinical scores showed a good to excellent result. In this small series total ankle replacement in patients with bleeding disorders show promising results. Further studies are needed to show the value of this relatively new type of surgery in haemophilic patients.

Mechanical testing of impaction bone grafting in the tibia: initial stability and design of the stem.

Clinical experience of impaction bone grafting for revision knee arthroplasty is limited, with initial stability of the tibial tray emerging as a major concern. The length of the stem and its diameter have been altered to improve stability. Our aim was to investigate the effect of the type of stem, support of the rim and graft impaction on early stability of the tray. We developed a system for impaction grafting of trays which we used with morsellised bone in artificial tibiae. Trays with short, long thick or long thin stems were implanted, with or without support of the rim. They were cyclically loaded while measuring relative movement. Long-stemmed trays migrated 4.5 times less than short-stemmed trays, regardless of diameter. Those with support migrated 2.8 times less than those without. The migration of short-stemmed trays correlated inversely with the density of the impacted groups. That of impaction-grafted tibial trays was in the range reported for uncemented primary trays. Movements of short-stemmed trays without cortical support were largest and sensitive to the degree of compaction of the graft. If support of the rim was sufficient or a long stem was used, impacted morsellised bone graft achieved adequate initial stability.

Are surgeons equally satisfied after total knee arthroplasty?

INTRODUCTION: We performed a clinical follow-up study to investigate whether three orthopaedic surgeons were equally satisfied after total knee arthroplasty (TKA). PATIENTS AND METHODS: Thirty-six patients (39 TKAs, mean follow-up 12 months) were reviewed, using the Knee Society Clinical Rating System (KSCRS). For the assessment of satisfaction a visual analogue scale (VAS) was used. RESULTS: We did not find a significant difference in satisfaction between the surgeons. However, there was a significant difference in the knee score and function score of the KSCRS as evaluated by the orthopaedic surgeons (p=0.006 and p=0.04, respectively). The correlation between the knee score and the surgeons' satisfaction was high, which indicates that pain, range of motion and deformity are important success criteria for surgeons. CONCLUSIONS: In this study, surgeons scored differently in the KSCRS but were equally satisfied after TKA.

Improvement in technique for arthroscopic ankle fusion: results in 15 patients.

We retrospectively assessed time until consolidation, complications, and functional results according to Morgan from the clinical charts and radiographs of 15 arthroscopic ankle fusions. In 11 patients unilateral distraction and crossed screw placement over the fusion area through tibia and fibula were used (group A); in 4 patients a technique of bilateral distraction and parallel screw placement from the dorsal side of the tibia into the neck of the talus was used (group B). In group A there were two cases of insufficient compression at the arthrodesis site, three cases of suboptimal compression, and five cases of malposition of the screws. In all cases in group B good compression and fixation was achieved, and no case of malpositioning of screws occurred. There was nonunion in 3 of 11 patients in group A and in none of the four patients in group B. Time until fusion was 23.3 in group A and 12.5 weeks in group B. Functional results were better in group B. The initial experiences with our technique of bilateral distraction and parallel screw placement are therefore promising. Screw placement is easier and optimal compression and fixation are achieved. We feel that this technique should be considered when performing an arthroscopic ankle fusion.

Open capsular shift for multi directional shoulder instability.

We evaluated the outcome of open antero-inferior capsular shift in 17 patients with multidirectional instability of the shoulder who failed to respond to conservative treatment. Six shoulders presented with secondary impingement syndrome and 11 with involuntary instability. The mean duration of follow-up was 39 months (range 7-89 months). Based on the Rowe and Constant scores and the 12-item questionnaire of Dawson, the results were rated excellent in 14 patients, fair in 2 and poor in 1. All but 2 patients were satisfied with the results, although 6 patients experienced some residual pain, and 4 suffered minor instability. There were no neurovascular complications, infections or symptomatic posterior instability. Open antero-inferior capsular shift yields promising short-term to medium-term results in multidirectional, involuntary instability of the shoulder.

Distal femoral bone mineral density after total knee arthroplasty: a comparison with general bone mineral density.

The bone mineral density (BMD) of the distal femur may decrease after cemented total knee arthroplasty (TKA) as a result of the stress shielding effect of the femoral component. The purpose of the study was to determine the changes in BMD of the distal femur compared with those of the femoral necks and the lumbar spine after cemented TKA. BMD of two regions of interest in the distal femur, both femoral necks and the lumbar spine was measured with dual-energy X-ray absorptiometry in 10 patients (age range 41-80 years, mean 62 years) with 12 TKAs preoperatively and during follow-up for 1 year after surgery. The hip and spine measurements were performed for comparison to assess if general changes in BMD occurred after TKA. The median decrease in BMD in the region behind the anterior flange of the femoral component was 22% (95% CI: 12%-33%), while the average decrease in the region just above the femoral component was 8% (95% CI: 2%-13%). The difference in change of BMD between both regions before and 1 year after TKA was significant (p = 0.03). We found less than 1% difference in BMD of both femoral necks and the lumbar spine on average between the preoperative and 1 year follow-up measurements (not significant). A significant periprosthetic distal femoral bone resorption occurred after TKA. BMD of the femoral necks and lumbar spine did not differ 1 year after TKA.

The GSB total knee arthroplasty. A medium- and long-term follow-up and survival analysis.

From 1981 to 1987, 77 GSB-II total knee arthroplasties were implanted in 65 patients. There were 23 men and 42 women aged on average 60 years old (range 30-85 years). The diagnosis was osteoarthritis (OA) in 21 knees, rheumatoid arthritis (RA) in 44 knees, and other in 12 knees. A clinical and radiological follow-up was performed in two stages after a mean of 6.7 years (61 knees) and 14.8 years (22 knees) to assess the medium- and long-term results and to determine if deterioration had occurred after mid-term follow-up. A survival analysis was done with two endpoints: (1) revision, and (2) revision, moderate or severe pain and lost to follow-up (worst-case scenario). At the last follow-up 36 patients (44 knees) had died, 2 patients (2 knees) refused examination, and 3 patients (3 knees) were lost to follow-up. Six knees had been revised for malposition (1.3%), septic (3.9%) and aseptic (2.6%) loosening. The mean Knee Society score after 6.7 and 14.8 years was 85 points (OA 82 points, RA 87 points). Lateralisation, subluxation or dislocation of the patella was present in 8 of 17 knees at the last follow-up. The 6- and 15-year survival rates with revision as the endpoint were 95% (CI 89%-100%) and 87% (CI 65%-100%), respectively. For the worst-case scenario, the 6- and 15-year survival rates were 95% (CI 89%-100%) and 56% (CI 0%-100%), respectively. The medium- and long-term results of the GSB-II total knee arthroplasty were good, and a decline in the knee score did not occur beyond the mid-term follow-up. Patella complications were abundant, and a marked decrease in implant survival was noted when moderate or severe pain and lost to follow-up were included as endpoints.

Synovial macrophage depletion with clodronate-containing liposomes in rheumatoid arthritis.

OBJECTIVE: To assess whether intraarticular (IA) administration of clodronate liposomes results in local macrophage depletion in patients with rheumatoid arthritis (RA). Primary goals were to address both the immunohistologic and potential toxic effects of this approach. Moreover, the correlation between immunohistologic findings and clinical assessments of disease activity and cartilage damage were assessed. METHODS: An open study was conducted in consecutive RA patients who were scheduled for knee joint replacement in our department. Synovial biopsy tissue was obtained from the knee joint at 2 weeks before and at the time of surgery. This protocol was controlled for safety and immunohistologic concordance in 6 patients. One week before surgery, 10 patients received a single IA dose of clodronate liposomes. Staining of synovial tissue for cell markers (CD68, CD14, CD3, CD38) and adhesion molecules (vascular cell adhesion molecule 1 [VCAM-1], intercellular adhesion molecule 1 [ICAM-1]) was assessed by 2 blinded observers. Local and systemic parameters of disease activity were measured before each intervention. Cartilage damage was scored using standard radiologic techniques at baseline and during surgery. RESULTS: A single IA dose of clodronate liposomes significantly reduced the number of CD68-positive cells (P = 0.005) and the expression of ICAM-1 and VCAM-1 in the synovial lining (P = 0.013 and P = 0.039, respectively). The intervention did not affect fibroblast-like synoviocytes, T cells, or plasma cells. No immunohistologic changes were observed in the control group. The procedure was well tolerated. The levels of ICAM-1 and VCAM-1 in the sublining layers correlated with the extent of macroscopic synovitis (P < 0.0005 and P < 0.005, respectively). The expression of ICAM-1 and CD14 in the sublining correlated with the levels of C-reactive protein (P < 0.0005 and P < 0.01, respectively). Cartilage destruction was correlated only with the expression of CD68 in the sublining (P = 0.02). CONCLUSION: A single IA administration of clodronate liposomes leads to macrophage depletion and decreased expression of adhesion molecules in the synovial lining in patients with longstanding RA. The procedure is well tolerated, and its therapeutic potential is currently under investigation. The expression of adhesion molecules in the sublining layers reflects ongoing inflammation.

Evaluating hand surgery in patients with rheumatoid arthritis: short-term effect on dexterity and pain and its relationship with patient satisfaction.

Short-term effect of hand surgery on hand function in activities of daily life (dexterity) and pain were studied in 70 patients with rheumatoid arthritis. Only surgical interventions aimed at improvement of function and/or pain relief were included in the study. Patients were assessed before surgery and 6 and 12 months after surgery. Clinical change in the surgical group was observed in the number of painful and swollen joints, observed dexterity, and pain in the hand. Six months after surgery 74% of the patients showed positive clinical change in hand functioning and/or hand pain. Clinical effects remained stable between 6 and 12 months after surgical assessments. Both change in observed dexterity and pain had an independent impact on the patient's satisfaction with the results of the surgery.

Impacted morsellized bone grafting and cemented primary total hip arthroplasty for acetabular protrusion in patients with rheumatoid arthritis: an 8- to 18-year follow-up study of 36 hips.

Between 1979 and 1989, we performed 36 primary total hip replacements in 31 rheumatoid arthritis patients with protrusio acetabuli. The deficient acetabulum was reconstructed with autologous morsellized bone grafts from the femoral head. 3 patients were lost to follow-up. 12 patients (13 hips) died within 8 years postoperatively, none had a revision. 16 patients (20 hips) were reviewed at an average follow-up of 12 (8-18) years. In 2 hips, a revision was performed for aseptic loosening of the acetabular component, 65 and 8 years after primary surgery, which means a 90% (95% CI: 77%-100%) survival rate at 12 years (Kaplan Meier analysis). This technique is a good option in cases with protrusio acetabuli due to rheumatoid arthritis.

Autologous morsellised bone grafting restores uncontained femoral bone defects in knee arthroplasty. An in vivo study in horses.

The properties of impacted morsellised bone graft (MBG) in revision total knee arthroplasty (TKA) were studied in 12 horses. The left hind metatarsophalangeal joint was replaced by a human TKA. The horses were then randomly divided into graft and control groups. In the graft group, a unicondylar, lateral uncontained defect was created in the third metatarsal bone and reconstructed using autologous MBG before cementing the TKA. In the control group, a cemented TKA was implanted without the bone resection and grafting procedure. After four to eight months, the animals were killed and a biomechanical loading test was performed with a cyclic load equivalent to the horse's body-weight to study mechanical stability. After removal of the prosthesis, the distal third metatarsal bone was studied radiologically, histologically and by quantitative and micro CT. Biomechanical testing showed that the differences in deformation between the graft and the control condyles were not significant for either elastic or time-dependent deformations. The differences in bone mineral density (BMD) between the graft and the control condyles were not significant. The BMD of the MBG was significantly lower than that in the other regions in the same limb. Micro CT showed a significant difference in the degree of anisotropy between the graft and host bone, even although the structure of the area of the MBG had trabecular orientation in the direction of the axial load. Histological analysis revealed that all the grafts were revascularised and completely incorporated into a new trabecular structure with few or no remnants of graft. Our study provides a basis for the clinical application of this technique with MBG in revision TKA.

Total knee arthroplasty in patients with inherited dwarfism--a report of five knee replacements in two patients with Morquio's disease type A and one with spondylo-epiphyseal dysplasia.

In Morquio's disease and in hereditary spondylo-epiphyseal dysplasia of longer duration, malalignment, instability and unfavourable anatomy are generally the main surgical problems, but as these patients nowadays do not have a reduced life expectancy, it is worthwhile giving them a functional replacement for their severely deformed and painful knees. We report three patients with inherited dwarfism, in whom a replacement of the knee was performed.

The kinematic total knee arthroplasty. A 10- to 15-year follow-up and survival analysis.

In 86 patients 102 consecutive cemented Kinematic total knee arthroplasties were reviewed 10-15 years after surgery to determine the clinical and radiographic results and to assess the survival rate. The average age of the 65 female and 21 male patients at the time of surgery was 63 years. Forty-six knees were affected by rheumatoid arthritis (RA), 46 by osteoarthritis (OA), 7 by haemophilic arthropathy and 3 by osteonecrosis. One patient (1 knee) was lost to follow-up, and 31 patients (38 knees) died. Eleven knees had been revised for deep infection (4), wear (4), malposition (2) or persistent pain (1). Fifty-two knees were examined at an average follow-up period of 12 years. The mean Knee Society Score of 89 points was the same for RA and AO knees. Also, 92% of the knees caused no pain or only occasional mild pain. There were no cases of aseptic loosening of any component. Progressive radiolucent lines were not seen on the follow-up radiographs (43 knees, mean follow-up 12 years) The 10- and 14-year survival rates with revision as the end-point were 90% (confidence interval, CI: 81%-95%) and 82% (CI: 67%-92%), respectively. In the worst case scenario, with knees lost to follow-up and knees with moderate pain considered as failures, the 10- and 14-year survival rates were 80% (CI: 69%-88%) and 62% (CI: 46%-77%), respectively. The Kinematic total knee arthroplasty yields equally good long-term results in patients with RA and those with OA. Deep infection and wear were the main reasons for revision.