Search

Abstract Background Hip dislocation after arthroplasty for femoral neck fractures remains a serious complication. The aim of our study was to investigate the dislocation rate in acute femoral neck fracture patients operated with a posterior approach with cemented conventional or dual articulation acetabular components. Methods We compared the dislocation rate in 56 consecutive patients operated with conventional (single mobility) cemented acetabular components to that in 42 consecutive patients operated with dual articulation acetabular components. All the patients were operated via posterior approach and were followed up to one year postoperatively. Results There were 8 dislocations in the 56 patients having conventional components as compared to no dislocations in those 42 having dual articulation components (p = 0.01). The groups were similar with respect to age and gender distribution. Conclusions We conclude that the use of a cemented dual articulation acetabular component significantly reduces the dislocation rates in femoral neck fracture patients operated via posterior approach.

Abstract Background While a relation between pain and intracapsular pressure in the hip joint has previously been reported by some of the present authors, a newly published study including patients with severe osteoarthritis was not able to confirm this finding. This stimulated us to investigate the role of short rotators in relation to intracapsular pressure and pain in osteoarthritic hips. Methods We measured the intracapsular hydrostatic pressure peroperatively in 25 total hip arthroplasty patients with severe osteoarthritis in various positions of the hip joint before and after short rotator release, and correlated these pressures to pain. Results Release of the short rotators did not change the intracapsular pressure in any position except in 45° flexion, in which the pressure increased (p = 0.002). We found no correlation between intracapsular pressure and pain before or after short rotator release. Conclusion We could not show that the rotators directly affected the pressure nor could we find a relation between pressure and pain.

Background: While a relation between pain and intracapsular pressure in the hip joint has previously been reported by some of the present authors, a newly published study including patients with severe osteoarthritis was not able to confirm this finding. This stimulated us to investigate the role of short rotators in relation to intracapsular pressure and pain in osteoarthritic hips.Methods: We measured the intracapsular hydrostatic pressure peroperatively in 25 total hip arthroplasty patients with severe osteoarthritis in various positions of the hip joint before and after short rotator release, and correlated these pressures to pain.Results: Release of the short rotators did not change the intracapsular pressure in any position except in 45 degrees flexion, in which the pressure increased (p = 0.002). We found no correlation between intracapsular pressure and pain before or after short rotator release.Conclusion: We could not show that the rotators directly affected the pressure nor could we find a relation between pressure and pain. [ABSTRACT FROM AUTHOR]

Introduction: The aim of this study was to investigate if preoperative measurements of the femoral valgus angle (FVA) affected the mechanical alignment, individual component positions and clinical outcome in total knee arthroplasty (TKA)., Methods: 120 patients were randomized into two groups. In one group (control), a fixed FVA for the intramedullary femoral guide was set at 7°, whereas in the other group (measured) FVA was measured preoperatively on long hip-knee-ankle radiographs, and the angle for the distal femoral cut was set accordingly. Preoperatively and 1 year after TKA, range of motion (ROM) and Knee Society Score (KSS) were assessed. Postoperatively, the coronal alignments of the components and the mechanical alignment were measured comparing the rate of outliers which deviated more than 3° from the neutral mechanical axis., Results: 104 patients remained for the radiological analysis (52 in each group). There were no significant differences either in the mean preoperative or postoperative mechanical alignment, or femoral or tibial component alignment; also, there were no differences in the number of postoperative mechanical axis or tibial component alignment outliers. However, the number of femoral component alignment outliers was significantly higher in the control group. 97 patients were available for clinical outcome analysis. Preoperatively, the groups did not differ significantly with respect to KSS or ROM. The postoperative ROM and KSS functional subscale scores were similar between the groups. However, there was slightly but significantly better postoperative KSS objective subscale score in the measured group., Conclusions: Preoperative FVA measurement and following femoral distal cut adjustments did not affect overall leg alignment postoperatively, while positioning of femoral component was improved together with minor improvements in objective KSS subscale scores.

Background and Purpose: The original Müller acetabular reinforcement ring (ARR) shows favorable medium-term results for acetabular reconstruction in total hip arthroplasty, where it is used when the acetabular bone stock is deficient. However, there are no data regarding long-term survival of the device. We therefore investigated long-term survival and analyzed radiological modes of failure., Patients and Methods: Between 1984 and 2002, 321 consecutive primary arthroplasties using an ARR were performed in 291 patients. The mean follow-up time was 11 (0-25) years, and 24 hips were lost to follow-up. For survival analysis, we investigated 321 hips and the end of the follow-up was the date of revision, date of death, or the last patient contact date with implant still in situ. Radiological assessment was performed for 160 hips with a minimum of 10 years of follow-up and with radiographs of sufficient quality. It included evaluation of osteolysis, migration, and loosening., Results: 12 ARR THAs were revised: 1 isolated ARR revision for aseptic loosening, 4 revisions of the ARR and the stem for aseptic loosening, 6 for infection, and 1 for recurrent dislocation. The cumulative revision rate for all components, for any reason, at 20 years was 15% (95% CI: 10-22), while for the ARR only it was 7% (95% CI: 4-12) for any reason and 3.4% (95% CI: 1-9) for aseptic loosening. 21 (13%) of 160 ARR THAs examined had radiological changes: 7 had osteolysis but were not loose, and 14 were radiologically loose but were not painful and not revised., Interpretation: Our data suggest that the long-term survival of the ARR is excellent.

Objective: To determine the rate ratios of hip and distal radius fractures in patients with rheumatoid arthritis (RA), hip osteoarthritis (OA), and knee OA., Methods: Cohort study using healthcare data (1998-2012) covering the entire population of the Skåne region of Sweden., Results: We found an increased rate of hip fracture in both female [standardized fracture rate ratio (SFR) 1.54, 95% CI 1.40-1.70] and male patients with RA (SFR 1.81, 95% CI 1.51-2.17). The hip fracture rate in female OA was reduced by 10-20%, and trochanteric fracture tended to have a higher rate ratio compared with the cervical., Conclusion: The 50-80% increased rate of hip fracture adds to the total burden of RA while the shifted distribution of cervical/trochanteric fractures in OA is in support of subchondral bone alterations.

Background and Purpose: The posterior soft tissue repair is 1 of the preventing factors for dislocation after total hip arthroplasty (THA).The aim of our study was to analyse THA patients with posterior soft tissue repair in terms of suture durability, time of suture failure and correlate the changes in leg length and offset postoperatively to suture durability., Methods: A total of 37 consecutive THA patients operated for osteoarthritis were included in the study. The posterior repair included reattaching the piriformis, conjoined tendons and posterior capsule to the greater trochanter through 2, 2 mm drill holes with 2 grasping stitches. A metal indicator wire was stitched into the piriformis tendon at distance of 1 cm from the greater trochanter after the prosthesis had been implanted and the joint reduced. Anteroposterior radiographs were taken immediately after the patients returned from the operating theatre to the intensive care unit, the next day after mobilisation, and at the 5th day of stay and at 3 months postoperatively., Results: Out of 37 THA hips, 6 (16%) had failed immediately after surgery, 25 (68%) at the 1st postoperative day after mobilisation, 2 (5%) at the 5th postoperative day, and 1 (3%) repairs had failed at 3 months after THA. In the remaining 3 hips no failure occurred., Interpretation: We conclude that posterior soft tissue repair in THA often fails and suggest that new posterior soft tissue repair methods be developed.

Background and Purpose: Postoperative muscle strength and component alignment are important factors affecting functional results after total knee arthroplasty (TKA). We are not aware of any studies that have investigated the relationship between them. We therefore investigated whether coronal malalignment of the mechanical axis and/or of individual implant components would affect knee muscle strength and function 1 year after TKA surgery., Patients and Methods: We included 120 consecutive osteoarthritis (OA) patients admitted for TKA. Preoperative active range of motion (ROM) of the knee, patient age, sex, and BMI were recorded and the Knee Society score (KSS) and knee joint extensor/flexor muscle strength were assessed. At 1-year follow-up, the mechanical and coronal component alignment was measured from a postoperative long standing radiograph, and ROM, KSS, and muscle strength measurements were taken in 91 patients. Functional outcome and muscle strength measurements were compared between normally aligned and malaligned TKA groups., Results: 29 of 91 TKAs were malaligned, i.e. they deviated more than 3° from the neutral mechanical axis. 18 femoral components and 15 tibial components were malaligned. Before surgery, the malaligned and normally aligned groups were similar regarding sex distribution, BMI, ROM, KSS, and muscle strength. At the 1-year follow-up, the differences between the groups regarding knee joint function and muscle strength were small, not statistically significant, and barely clinically relevant., Interpretation: Moderate varus/valgus malalignment of the mechanical axis or of individual components has no relevant clinical effect on function or muscle strength 1 year after TKA surgery.

The aim of our study was to investigate the dynamics of cortical thinning around well fixed cemented Muller straight stems without osteolysis at different time periods during long term follow-up. We investigated patients operated on for osteoarthritis with a cemented Muller straight stem, all with more than 15 years follow-up and no radiological signs of osteolysis. Cortical thinning in 20 THA hips (19 patients) followed for a mean of 20 (16 to 22) years was measured medially and laterally at six levels from the first postoperative, five, 10 years and the last follow-up x-rays. Sixty percent of observed cortical thinning occurred during the first five postoperative years, which was more evident proximally. We conclude that significantly greater cortical bone loss occurs around cemented Muller straight stems during the first five years, than is seen subsequently. We feel that this is a non-pathological process mainly related to the Muller straight stem.

Background: Previously was found that sonography is a reliable method to measure a capsular distance in total hip arthroplasty hips. The aim of our current study was to investigate the relation between the implanted size of the cup and the anterior capsular distance, as measured with ultrasound one year after THA., Methods: 50 osteoarthritis (OA) patients operated on with total hip arthroplasty one year before were included in the study and the anterior capsular distance was measured sonographically. Patients were grouped with respect to cup size. The correlation between the implanted cup size and capsular distance was determined., Results: The mean capsular distance in the whole group was 1.37 (SD 0.19) cm. The mean capsular distance in the group with small cups was 1.27 (SD 0.13) cm, in large cups it was 1.45 (SD 0.20) cm, p = 0.02. Spearman correlation analysis showed a statistically significant correlation between a greater capsular distance and the larger size of the cup (r = 0.5, p < 0.0001)., Conclusion: The greater capsular distance in successful THA hips is affected by cup size. We propose that this should be considered when evaluating sonography of the anterior capsular distance after THA.

Total hip arthroplasty for intracapsular femoral neck fractures (FNF) is associated with a greater risk of dislocation. Dual articulation systems in this group of patients may provide better implant stability and a reduced dislocation rate. The aim of our study was to investigate FNF patients treated with dual articulation cups (DAC) and conventional THA and compare their clinical results at four months and one year after surgery. Our study compared femoral neck fracture patients treated with either DAC or conventional THA during two different time periods. Before surgery and during follow-up, the patients answered questions regarding their mobility, pain and usage of walking aids. Additionally at four-month and one-year follow-ups EQ-5D and HOOS questionnaires were applied for those patients qualifying for functional and quality of life analysis. Out of 125 femoral neck fracture patients 58 were treated with DAC and 67 with conventional THA. At four months and one year follow-up the HOOS and EQ-5D results did not differ significantly between DAC and conventional THA. Five hips in the THA group were revised for recurrent dislocation and two had a single dislocation. One year after surgery, the functional result of DAC and conventional THA are comparable but DAC have a lower risk of dislocation.

A randomised controlled trial was performed to investigate if the short rotators affected the compliance of the capsule in osteoarthritis (OA). 68 OA patients admitted for total hip arthroplasty (THA) were randomised to have their compliance estimated during surgery with either their short rotators intact or released. Radiographic severity of OA, range of motion and pain were assessed in the affected hip before surgery. There was no significant difference in the compliance of the capsule whether the short rotators were intact or released (p= 0.5). Furthermore, there was no significant correlation between pain and capsular compliance (p=0.4 and p=0.5). We found no significant effect of the short rotators on compliance of the hip joint capsule, and no significant correlation between pain and capsular compliance.

Posterior soft tissue repair is a well-known procedure in total hip arthroplasty (THA). Many reports have shown the advantage of posterior soft tissue repair in reducing the dislocation rate; however, we were unable to find any randomized trials in the literature. This article describes a randomized trial performed to investigate the effect of posterior soft tissue repair on the dislocation rate after 298 THAs in 291 patients. Preoperatively, patients were randomized into 2 groups: posterior soft tissue repair after insertion of the components, or no posterior soft tissue repair. One year postoperatively, 12 patients had died and 10 were lost to follow-up, leaving 276 THAs in 265 patients for analysis. A posterior soft tissue repair had been performed in 134 and no repair in 141 THA. One year postoperatively, 3 dislocations (2%) had occurred in the repaired group and 7 in the unrepaired group (5%); the difference was not significant (P=.3). There were 2 sciatic nerve palsies in the repaired group, 1 of which was directly related to the posterior soft tissue repair.In this randomized, controlled trial of 276 THAs followed for 1 year, there was a tendency for a lower dislocation rate, although not statistically significant, when a posterior repair was performed. If reattaching the posterior tendons, it should be performed with caution with respect to the sciatic nerve., (Copyright 2010, SLACK Incorporated.)

Background: Hip dislocation after arthroplasty for femoral neck fractures remains a serious complication. The aim of our study was to investigate the dislocation rate in acute femoral neck fracture patients operated with a posterior approach with cemented conventional or dual articulation acetabular components., Methods: We compared the dislocation rate in 56 consecutive patients operated with conventional (single mobility) cemented acetabular components to that in 42 consecutive patients operated with dual articulation acetabular components. All the patients were operated via posterior approach and were followed up to one year postoperatively., Results: There were 8 dislocations in the 56 patients having conventional components as compared to no dislocations in those 42 having dual articulation components (p = 0.01). The groups were similar with respect to age and gender distribution., Conclusions: We conclude that the use of a cemented dual articulation acetabular component significantly reduces the dislocation rates in femoral neck fracture patients operated via posterior approach.

Background and Purpose: Reports regarding the relationship between delayed surgery and mortality in femoral neck fracture patients are contradictory. We could not find any study in the literature investigating delayed arrival to hospital and delayed surgery as separate factors affecting mortality in femoral neck fracture patients, which was the purpose of our study., Patients and Methods: We analyzed 265 consecutive patients with displaced femoral neck fractures. We recorded the time period from trauma to admission, and to surgery, and correlated it to mortality during the first postoperative year., Results: We found that arrival within 6 hours had 0.4 times (CI 0.2-0.8) reduction of the risk of death within 1 year compared to those who arrived later, whereas delayed surgery after admission did not have a statistically significant effect on mortality., Interpretation: Femoral neck fracture patients who arrived at hospital 6 hours or later after the trauma had increased mortality.

Total knee replacement in severe osteoarthritis usually requires extensive soft tissue releases often associated with considerable bleeding. In a prospective, randomised trial we compared postoperative conventional suction drainage versus four hour clamping drainage in 60 patients undergoing total knee arthroplasty for severe osteoarthritis. We compared blood loss, number of transfusions, postoperative complications and knee function and found significantly less postoperative blood loss through the drains (p < 0.001), and fewer blood transfusions (p = 0.09) were needed in the clamped group. We conclude that clamping drainage after total knee arthroplasty in severe osteoarthritis reduces blood loss through the drains and the need for blood transfusions.

Background and Purpose: We have previously reported that the first 10 years of hip arthroplasty in Lithuania resulted in a higher cumulative revision rate than that observed in Sweden. We thus compared the corresponding results after introduaction of total knee replacement in Lithuania., Methods: The 10-year revision rate for the first 595 primary ScanKnee arthroplasties inserted in Klaipeda, Lithuania, was compared to that for the first 1,280 ScanKnee primary arthroplasties inserted in Sweden. As in the hip replacement study, only patients with osteoarthritis (OA) were included. Primary knee arthroplasties without patellar resurfacing were included, and the endpoint was revision for any reason other than addition of a patellar component., Results: We found that the cumulative revision rate was not statistically significantly different between the groups. The revision pattern was different, however, and we observed 24 isolated patellar component additions in Sweden, but none in Klaipeda., Interpretation: Contrary to the results of our previous hip arthroplasty study, the cumulative revision rate after total knee arthroplasty was similar in the two groups. This suggests that compared to hip arthroplasty, the outcome of total knee arthroplasty was less dependent on surgical experience. The large difference regarding isolated patellar component additions may be explained by long-term accumulation of severe OA cases in Lithuania. To patients subject to a newly introduced surgical treatment offering great improvement in quality of life, patellofemoral pain may be a minor problem. Furthermore, patellar problems may not have seemed particularly relevant for the surgeons, considering the disability of other patients waiting to be treated.

Hip fractures are a major cause of hospital stay among the elderly, and result in increased disability and mortality. In this study from 1 April 2003 to 31 March 2004, the influence of optimised treatment of hip fracture on time to operation, length of hospital stay, reoperations and mortality within 1 year were investigated. Comparisons were made between the first 210 patients in the period and the last 210 patients, who followed the new clinical pathway introduced at the University Hospital in Lund, Sweden. Early surgery, within 24h, was not associated with reduced mortality, but was significantly associated with reduced length of stay (p<0.001). Significantly more cases of osteosynthesis for femoral neck fracture were reoperated compared with all other types of surgery (p<0.001) when reoperations with extraction of the hook pins in healed fractures were excluded. Mortality was significantly higher among men than women at 4 (p=0.025) and 12 (p=0.001) months after fracture and among medically fit patients with administrative delay to surgery compared with patients with no delay (p<0.001).

Background and Purpose: The role of synovitis and high fluid pressure in the loosening process after total hip arthroplasty has gained increasing attention. We investigated the correlation between head size, polyethylene wear, and capsular distention., Patients and Methods: We analyzed 39 unrevised, radiographically stable hips that had been operated with 28 or 32 mm femoral heads 10 years earlier because of osteoarthritis. We evaluated radiographic signs of loosening, linear and volumetric polyethylene wear, body mass index, activity level, and age. Sonographic examination was performed to measure capsular distance i.e. the distance between the prosthetic femoral neck and the anterior capsule., Results: Linear wear was 0.09 mm/year and 0.18 mm/year in the 28 mm and 32 mm groups, respectively (p < 0.001). The volumetric wear was 51 mm(3)/year and 136 mm(3)/year (p < 0.001) and the capsular distance was 13 mm and 17 mm, respectively (p < 0.001). There was a correlation between linear wear (r = 0.54), volumetric wear (r = 0.62), and capsular distance (p < 0.001)., Interpretation: Wear was greater for the larger femoral head and was correlated to capsular distension.

Background: Hip replacement as a routine procedure was introduced in Lithuania in 1991. At Klaipeda Hospital, one of the 2 hospitals at which this was begun, the arthroplasties were followed prospectively from the start. This study concerns the 10-year results from a country with no previous experience of hip replacement. The results are compared with those from a hospital with considerable experience of total hip replacement., Methods: We compared the revision rate for the first 658 primary ScanHip arthroplasties inserted at Klaipeda to that for the first 939 ScanHip primary arthroplasties inserted at Lund University Hospital, Sweden. Only patients with osteoarthritis were included, and the endpoint was revision for aseptic loosening with exchange of one or both components., Results: We found that patients operated at Klaipeda Hospital had a significantly higher risk of revision (12%) than those operated in Lund (6%)., Interpretation: Although we could not identify any specific reason for the Swedish results being better than the Lithuanian results, it is probable that previous surgical inexperience of hip replacement in Lithuania played a role. We believe that the findings will stimulate surgeons in Lithuania to analyze their failures and improve the results.

We investigated intracapsular pressure and elasticity of the hip joint capsule in osteoarthritis. HOOS hip score, sonography of the hip joint, and radiographic assessment of osteoarthritis were performed in 31 patients before total hip arthroplasty. The intracapsular hydrostatic pressure was measured perioperatively, and 0.9% saline solution was then injected in the hip joint, 1 mL at a time, with continuous pressure recording up to 300 mm Hg. The mean radiographic grade of severity of osteoarthritis was 8 (SD, 2.4). The mean hydrostatic intracapsular pressure in 45 degrees of flexion was 2.2 mm Hg (SD, 10.0); in extension, 15.8 mm Hg (SD, 33.0); in inward rotation, 13.7 mm Hg (SD, 26.0); and in outward rotation, 12.1 mm Hg (SD, 24.3). Severe osteoarthritis was associated with lower intracapsular pressure and lower elasticity of the joint capsule.

Background: Excessive mortality and morbidity are serious problems after hip fracture in the elderly., Methods: Hip fractures in persons aged 50 years or older were prospectively registered in Japan in 2000. Questionnaires regarding both the first onset and the second 120-day period after hip fracture were obtained from 759 patients, 546 of whom were female and 213 male., Results: Their average age at the time of fracture was 80 years. Altogether, 68 people (9%) died within 120 days after fracture; and 25 patients died within 30 days. Those dying within 120 days and those alive after hip fracture were compared. By univariate analysis, risk factors were poor walking ability, need for a walking aid, low body mass index, history of falls, and lack of active exercise; however, none of these factors was identified as a risk factor by multivariate analysis. By multivariate analysis, the five risk factors associated with mortality were male sex, older age, high American Academy of Anesthesiology (ASA) grade, dementia, and residence in an institution., Conclusions: During the treatment and rehabilitation period special attention should be paid to patients with chronic diseases and reduced mental status.

Objective: To compare implant survival rates after total hip arthroplasty with Exeter matte or polished stems and to determine the relationship of synovitis/joint effusion to signs of implant loosening and stem type., Material and Methods: The first part of the study included retrospective revision rate analysis of 118 primary hip replacements performed during 1991-1995. Two different designs of Exeter stems were used: matte surface stems during 1991-1995 (matte surface group--47 cases), and polished stems during 1992-1995 (polished stem group--71 cases). During the second part of the study, 24 patients (11 in polished stem group and 13 in matte stem group) were prospectively examined with radiography and sonography. Sonography was performed in order to evaluate capsular distension, i.e. the distance between prosthetic femoral neck and anterior capsule. Capsular distension depends on synovitis and/or synovia in prosthetic hip. The relationship between capsular distension, stem type, and radiographic signs of loosening was assessed., Results: For the first part of our study, total implant survival was 78% with matte stems and 61% with polished stems 13 years postoperatively (P=0.27). Stem survival was 82% for matte stems, and 88% for polished stems (P=0.54). In the second part of study, a significant relationship between increased capsular distension and cup loosening was determined (P=0.04). We did not find significant difference in capsular distension when compared matte and polished stems., Conclusion: Implant survival rates did not differ between the groups. The relationship between capsular distension and cup loosening was statistically significant.

Dislocation after total hip replacement is more common in the early, postoperative period. Postoperative intraarticular haematoma and remaining seroma fluid and/or weakened posterior soft tissue wall may be contributing factors. Our purpose was to compare and follow with sonography the resorption of the postoperative volume of intraarticular fluid/synovial oedema after total hip arthroplasty (THA) with or without posterior soft tissue repair. Thirty-three consecutive patients with hip osteoarthritis were admitted for THA. All of them received the same type of cemented implant. Patients were randomised for posterior soft tissue repair or not. Sonography, measuring the anterior capsular distension, indicating the volume of intraarticular fluid/synovial oedema in the prosthetic hip joints, was performed after six and 12 months in all patients. At six months postoperatively greater capsular distension, i.e., remaining volume of intraarticular fluid/synovial oedema, was observed in the group with posterior soft tissue repair than in the group without. After one year the capsular distension had decreased in both groups and there was no significant difference between the groups. Our results show that posterior soft tissue repair after THA is associated with increased capsular distension during the first six months. After 12 months the volume of intraarticular fluid/synovial oedema is the same with or without posterior soft tissue repair.

We measured in vivo polyethylene wear of acetabular cups in 74 patients (83 hips) with Charnley total hip arthroplasties (THA), revised because of aseptic loosening of either the acetabular or femoral component. We analyzed conventional pelvic radiographs of 42 THAs before revision due to loose acetabular components alone and 41 THAs before revision due to loose femoral components alone. The THAs were revised after 10 to 26 years. The mean wear-rate in hips with a loose acetabular components was 0.3 mm/y, whereas in hips with a loose femoral components, it was 0.1 mm/y (P=.0001). The mean total linear wear, as measured on the last available radiographs before revision, was 3.4 mm and 1.5 mm, respectively (P=.0001). A significant difference in linear wear between hips with loose cups and loose stems was seen 1 year after surgery: 0.4 mm/y versus 0.3 mm/y, respectively (P=.05)., (Copyright 2003, Elsevier Science (USA). All rights reserved.)

Our aim was to compare hemiarthroplasty (HA) and osteosynthesis (OS) in the treatment of cervical hip fractures using matched-pair analysis, especially with regard to different age groups. Data concerning all hip fractures (excluding pathological fractures) at the University Hospitals of Lund in Sweden, where osteosynthesis with LIH hook-pins was used exclusively, and of Oulu in Finland, using mainly cementless Austin-Moore hemiarthroplasty, were registered during 1989-1996 using the same standardized hip fracture forms filled in preoperatively and at 4 months follow-up. Altogether 446 pairs matched for age, sex, place of residence and walking ability at the time of fracture were found. Patients aged 55-80 years seemed to benefit more, with regard to function, from OS than older patients. At 4 months follow-up, 38% of HA and 48% of OS patients lived in their own homes, 16% and 27% were able to walk alone outdoors, and 11% versus 16% were able to walk without any aids, respectively. At 1 year follow-up, mortality was significantly lower among the OS patients, but the reoperation rate was significantly higher. In conclusion, OS is associated with a better function and lower mortality than HA, especially in younger patients, and it is recommended as the primary treatment for cervical hip fractures in patients younger than 80 years and with good ambulatory capacity, whereas the oldest patients can also be safely treated by HA.

We analyzed the radiographic and clinical outcome of the ScanHip total hip arthroplasty in 70 patients after 10 years. The Swedish National Hip Register, in which the end-point of the survival analysis is defined as revisions, reported a 10-year survival rate of 94% with the ScanHip, but in the present series 13% of the femoral stems and 29% of the sockets met the criteria for aseptic loosening. Focal osteolysis was found around 8 sockets (11%) and 23 stems (32%) and had occurred significantly oftener around loose sockets, but not around femoral stems. Linear polyethylene wear was significantly increased in loose sockets, but no relationship was noted between polyethylene wear and stem loosening or was there a correlation between clinical symptoms or patients' satisfaction and component loosening. Therefore precise serial long-term radiographic follow-up is the only satisfactory method for detecting aseptic loosening of total hip arthroplasty. It gives the surgeon more detailed information about each case than survival analysis alone.

Data of 1,337 consecutive hip fracture patients were registered during 1 year within a prospective comparative multicenter study comparing osteosynthesis techniques and rehabilitation results in Budapest, Hungary, in Sundsvall, northern Sweden, and in Lund, southern Sweden. In Budapest the mean age was 4-5 years lower than in Sweden, and more patients lived in their own home (91% versus 70% and 62%). Less intracapsular (41% versus 54% and 54%) and more trochanteric fractures (52% versus 40% and 35%) were observed in Budapest. Many more Hungarian patients returned home (68% versus 54% and 33%); however, their mortality rate 4 months later significantly exceeded that of the Swedish centres (24% versus 15% and 13%), and more had severe pain in the operated hip (27% versus 17% and 15%). Four months after double nail osteosynthesis of displaced cervical fractures, more patients (28%) had severe hip pain than after hemiarthroplasty (16%) in Budapest as compared to Lund or Sundsvall (19% and 22%). Mortality rate after 4 months following hemiarthroplasty and nailing (36% and 20%) was significantly higher than in the Swedish centres (14% and 11%).

The articulating surfaces of 6 ultra-high molecular weight polyethylene cups were exposed to curing polymethyl methacrylate (PMMA) bone-cement and examined with scanning electron microscopy and laser ablation inductively coupled plasma mass spectrometry (LA-ICPMS). Three of the cups were exposed to blood and bone-cement, and the rest were exposed to bone-cement only. After removal of the bone-cement bulk, PMMA particles were found and identified in all 6 cups. The particles were verified by identifying zirconium with energy-dispersive x-ray fluorescence spectroscopy in 5 cups and with LA-ICPMS in 1 cup. The degree of surface contamination was estimated with LA-ICPMS. The number of zirconium-containing particles detected was on average 10 to 20/mm2. PMMA bone-cement left in polyethylene cups during polymerization can contaminate the articulating surface with adherent PMMA particles.

Synovitis is an important feature in Legg-Calvé-Perthes disease (LCPD) with a significant prognostically negative impact on clinical symptoms, cartilage biochemistry, mechanical properties of the cartilage, joint biomechanics, and prognosis toward healing with a congruent, spherical head of femur. Synovitis causes cartilage edema, deterioration of the cartilage's mechanical properties, cartilage hypermetabolism, and, subsequently, cartilage hypertrophy. This sequence of events could explain the clinical course, which consists of cartilage hypertrophy, lateral subluxation, anterolateral deformation of the head, and, subsequently, joint incongruence in prognostically poor cases of LCPD. A factor in the deformation of the hypertrophic cartilage of the epiphysis is decreased range of motion of the hip, because of pain caused by the increase in intracapsular pressure and the subsequent decrease in the "molding" ability of the acetabulum. Synovitis in LCPD causes an increased intracapsular pressure, the magnitude of which may, in some patients, intermittently compromise the blood supply to the proximal femoral epiphysis. Whether synovitis is the consequence of, or precedes, the loss of blood supply and epiphyseal necrosis is not yet established. Significant and persistent synovitis during the entire course of the disease emphasizes the importance of magnetic resonance imaging as the method of choice for the diagnosis and the prognosis, as well as the monitoring of therapy. The prognostically negative effects of synovitis suggest that more therapeutic efforts should be focused on the treatment of synovitis, from a palliative and prognostic point of view.

Forty-six patients (48 hips), operated on with cemented total hip arthroplasty (THA) because of arthrosis, were examined radiographically and sonographically at 10-year follow-up. Polyethylene wear of acetabular cups was measured on conventional non-weight-bearing pelvic radiographs, and the volume of polyethylene debris was calculated. Radiographic signs of loosening were identified. The capsular distance (ie, thickness of the synovium or synovial contents) was measured sonographically. We found a significant correlation between increased volumetric wear and increased capsular distance. Hips with radiographically loose acetabular components had significantly greater volumetric wear and capsular distance than those without signs of acetabular loosening. This relationship was not observed in hips with radiographically loose femoral components. In cemented THA, the volume of polyethylene wear debris and the thickness of the synovium and the synovial contents are related. In the event of radiographic loosening of the acetabular component, they are both increased.

We analyzed the cumulative revision rate in 1,474 patients (1,660 hips) operated on with a cemented Scan Hip Classic I prosthesis from November 1983 to January 1994 at Lund University Hospital. The revision rate was analyzed for 3 diagnoses--arthrosis, rheumatoid arthritis and complication after a hip fracture--and for 2 head diameters--22 and 32 mm. Until January 1996, 36 hips were revised: 31 because of aseptic loosening, 3 because of dislocation and 2 because of infection. The overall revision rate was 5.6% after 10 years and was similar in arthrosis, rheumatoid arthritis and fracture cases. Due to revisions because of dislocation in the 22 mm group, the total revision rate was lower in the 32 mm group (p = 0.03).

EBRA (Ein Bild Röntgen Analyse) is a new computerized method measuring migration and wear of the acetabular cup, suggested to improve measurement accuracy. We evaluated possible errors of measurement and compared EBRA with standard methods. 1. We did repeated measurements on a single radiograph using the same reference lines. The reliability of the input procedure with standard measurements was significantly better than repeated digitization with EBRA. 2. In a more clinical test, a group of 10 patients was studied. 5 radiographs were taken of the same patient on the same day. EBRA improved the reliability of repeated radiographic examination significantly for migration measurements in the vertical direction. 3. To assess the inter- and intraobserver variations, repeated measurements were performed on the clinical series of pelvic radiographs of 10 patients. EBRA was significantly better than standard methods. With EBRA, errors of wear and migration measurements could be reduced, as compared to standard methods. The major improvement with EBRA was found for migration measurements in the vertical direction.

One thousand one hundred sixty-nine elderly Japanese patients who sustained a hip fracture were observed prospectively. Ninety-two percent had operative fracture treatment. Hospital length of stay averaged 67 days; 81% of patients were discharged to their place of residence where they resided before sustaining the fracture. Mortality rates at 120 days, 1 year, and 2 years after injury were 6%, 11%, and 19%, respectively. At 1-year followup, ambulatory status was recovered to that of the level experienced before injury in 67% of patients.

We studied 21 children with Legg-Calvé-Perthes Disease with a prognostically poor development, including lateralization, poor containment, anterolateral flattering, and deformation of the femoral head, as evaluated on serial magnetic resonance (MR) imaging. These children were treated with proximal femoral varus derotation osteotomy. The sphericity of the cartilaginous and bony femoral epiphysis was evaluated postoperatively on serial radiography and MR imaging. There was an early postoperative continuous spherical remodeling over a follow-up period of 3.0 years (1.0-5.1; SD, 1.3).

Intracapsular hip joint pressure was measured in six infants with congenital dislocation of the hip (CDH) or acetabular dysplasia with hip joint instability diagnosed at an average of 4.3 months of age (range: 3-8 months). In the extension and neutral rotation position, the mean pressure was 8.9 mm Hg. After reduction, obtaining stability with the hip joints in the "frog-leg" position (i.e., maximum flexion around the axis of the neck of the femur), the mean pressure was 74.6 mm Hg. When obtaining stability with the hip joints in 20 degrees of flexion, abduction, and inward rotation, the mean pressure was 104 mm Hg, and in approximately 20 degrees of flexion, abduction, and forced inward rotation it was 160 mm Hg. We conclude that these rotational positions, often used to retain the joint in CDH or hip joint instability, induce intracapsular pressures that may cause occlusion of epiphyseal-physeal vessels and thus may be responsible for the avascular epiphyseal necrosis and growth disturbance seen in these patients.

We measured the intracapsular pressure preoperatively in 18 hips (17 patients) before revision of a total hip arthroplasty because of aseptic loosening. Distension of the joint capsule was measured with sonography in 13 cases. In extension, the mean intracapsular pressure was 26 (0-60) mmHg, in extension and inward rotation it was 159 (24-280) mmHg, in extension and outward rotation it was 30 (3-67) mmHg and in 45 degrees of flexion it was 12 (0-28) mmHg. A mean of 6 (0.5-20) mL of joint fluid was aspirated after the pressure measurements. Sonography showed increased joint fluid/synovial edema and/or increased capsular thickness, as compared to 34 unrevised, radiographically not loose prosthetic hips, and that the capsular distension correlated to intracapsular pressure during extension and inward rotation. We conclude that the intracapsular pressure usually is elevated in a hip joint with loose prosthetic components, that the intracapsular pressure varies with the position of the hip and that capsular distension reflects increased intracapsular pressure. The increased and often very high pressure, varying during gait, may pump debris away from the joint along the interfaces and even by itself cause osteolysis and loosening.

Long-term pain problems and residual restricted mobility were evaluated for patients sustaining acute distractive flexion injuries to the cervical spine. To assess which of two alternative surgical approaches gives better long-term outcomes, 58 patients were studied, 29 in each group. The results of posterior wire stabilization without fusion according to Brandt were contrasted with those of the Cloward technique. We found significantly more late pain problems and restricted neck mobility in the group treated with wiring without fusion than in those managed with anterior fusion. We conclude that this continuing pain may be due to residual mobility in the damaged degenerated non-fused motion segment, and that the difference between the two groups may reflect the difference in the quality and rate of fusion achieved by the two surgical approaches.

Growth in 110 children with Legg-Calve-Perthes' disease (LCPD) was longitudinally followed throughout the growth period. The infancy childhood puberty (ICP) growth model, which has the advantage that reference values can be adjusted for the individual age at pubertal maturation, was used. On the average, the children were slightly shorter at birth and they remained short throughout the entire growth period to maturity. At maturity, the boys were 4.4 cm and the girls were 2.5 cm below the reference mean. The growth velocity was normal at the time of diagnosis, prepubertally, and during puberty. Boys and girls differed only in that the boys were more overweight.

We measured radiographic polyethylene wear in patients with Scanhip arthroplasty and no clinical or radiographic signs of loosening. The patients were divided into 2 groups according to head sizes. 32 patients (33 hips) had an implant with a 22 mm and 30 patients (34 hips) with a 32 mm head. They were followed for 7-9 years. The groups were matched for diagnosis, sex, weight, age, and time of follow-up. The mean linear wear with a 22 mm head was 1.1 mm and with a 32 mm head 1.5 mm (p 0.004), which corresponds to a yearly wear rate of 0.15 mm and 0.18 mm, respectively. The mean difference in volumetric wear was greater, 420 mm3, as compared to 1239 mm3.