More complications with uncemented than cemented femoral stems in total hip replacement for displaced femoral neck fractures in the elderly.

Background and purpose - Total hip replacement (THR) is the preferred method for the active and lucid elderly patient with a displaced femoral neck fracture (FNF). Controversy still exists regarding the use of cemented or uncemented stems in these patients. We compared the effectiveness and safety between a modern cemented, and a modern uncemented hydroxyapatite-coated femoral stem in patients 65-79 years of age who were treated with THR for displaced FNF. Patients and methods - In a single-center, single-blinded randomized controlled trial, we included 69 patients, mean age 75 (65-79) and with a displaced FNF (Garden III-IV). 35 patients were randomized to a cemented THR and 34 to a reverse-hybrid THR with an uncemented stem. Primary endpoints were: prevalence of all hip-related complications and health-related quality of life, evaluated with EuroQol-5D (EQ-5D) index up to 2 years after surgery. Secondary outcomes included: overall mortality, general medical complications, and hip function. The patients were followed up at 3, 12, and 24 months. Results - According to the calculation of sample size, 140 patients would be required for the primary endpoints, but the study was stopped when only half of the sample size was included (n = 69). An interim analysis at that time showed that the total number of early hip-related complications was substantially higher in the uncemented group, 9 (among them, 3 dislocations and 4 periprosthetic fractures) as compared to 1 in the cemented group. The mortality and functional outcome scores were similar in the 2 groups. Interpretation - We do not recommend uncemented femoral stems for the treatment of elderly patients with displaced FNFs.

Cemented compared to uncemented femoral stems in total hip replacement for displaced femoral neck fractures in the elderly: study protocol for a single-blinded, randomized controlled trial (CHANCE-trial).

BACKGROUND: Total hip replacement (THR) is the preferred method for the active and lucid elderly patient with a displaced femoral neck fracture (FNF). But controversy still exists regarding using cemented or uncemented stem in these patients. The aim of this study is to compare a cemented and uncemented femoral stem in patients 65-79 years treated surgically with THR for displaced FNF. METHODS/DESIGN: In a single-centre, single-blinded, randomized controlled trial, we will include 140 patients aged 65-79 years with an acute displaced FNF and randomize them in a 1:1 ratio to a cemented tapered or a uncemented tapered hydroxyapatite - coated femoral stem. A cemented cup will be used in both groups. The patients will be blinded for allocation. The primary endpoints will be the incidence of all hip-related complications and health-related quality of life evaluated with EuroQol-5D (EQ-5D) index up to 2 years after surgery. Secondary outcomes will be overall mortality, general medical complications and hip function. The follow-up will be at 3 months, 1 and 2 years. Further follow-ups after end of study will be at 4 and 10 years. Results will be analysed using 95 % CI's for the effect size. A regression model will also be used to adjust for stratification factor. DISCUSSION: The ethical committee at Karolinska Institutet has approved the study. An interim analysis on the primary endpoints will be performed when half the sample size is included. The results from the study will be disseminated to the medical community via presentations and publications in relevant medical journals. The study will provide evidence if a cemented or uncemented femoral stem is preferable in THR for elderly patients with a displaced FNF. TRIAL REGISTRATION: The trial is registered at clinicaltrials.gov ( NCT02247791 ), October 21, 2013.

Denosumab for treating periprosthetic osteolysis; study protocol for a randomized, double-blind, placebo-controlled trial.

BACKGROUND: Wear-induced osteolysis is the main factor in reducing the longevity of total hip arthroplasty (THA). The transmembrane Receptor Activator of Nuclear Factor κ B (RANK) and its corresponding ligand RANKL is an important regulator of osteoclast activity and bone resorption and is associated with osteolysis around implant. Inhibiting RANKL with denosumab is effective in vivo in preventing osteoporosis-related fractures. In vitro, osteoclasts can be blocked in animal models of osteolysis. We hypothesize that denosumab is effective in reducing wear-induced osteolysis around uncemented acetabular implants in THA. METHODS/DESIGN: A randomized, double-blind, placebo-controlled trial will be conducted. We will include 110 patients, 40-85 years of age, with a known osteolytic lesion around an uncemented acetabular component ≥7 years after the primary operation. The patients will be randomized in a 1:1 ratio to subcutaneous injections of 60 mg denosumab or placebo for a total of 6 doses with start on day one and every 6 months with last treatment at 30 months. The primary endpoint will be the change in volume of the osteolytic lesion at 3 years measured with three-dimensional computed tomography (3D-CT). Secondary endpoints include functional outcome scores, change in bone mineral density of the lumbar spine, serological markers of bone turnover and adverse events. DISCUSSION: In vitro results of both bisphosphonates and RANKL inhibitors have been promising, showing reduced osteolysis with treatment. This is, to our knowledge, the first clinical trial testing the efficacy of denosumab in reducing wear-induced osteolysis. The study is an academic, phase II trial from an independent center and is designed to demonstrate efficacy in reducing volume of osteolytic lesions around a total hip arthroplasty. TRIAL REGISTRATION: ClinicalTrials.gov (NCT02299817) 2014-11-20.

HOPE-trial: hemiarthroplasty compared to total hip arthroplasty for displaced femoral neck fractures in the elderly-elderly, a randomized controlled trial.

BACKGROUND: A femoral neck fracture (FNF) is a common cause of suffering and premature death in the elderly population. Optimizing the treatment for improved outcome and a reduced need for secondary surgery is important both for the patient and the society. The choice of primary total or hemiarthroplasty in patients over eighty years are controversial. We hypothesized that total hip arthroplasty has an equal or better outcome in patient-reported outcome compared with hemiarthroplasty. METHODS/DESIGN: A prospective, randomized, single-blinded trial will be conducted. We will include 120 patients, 80 years of age and over with an acute (<36 h) displaced femoral neck fracture. The patients will be randomized in a 1:1 ratio to either total hip arthroplasty or hemiarthroplasty. The primary endpoints are Harris hip Score and EQ-5D. Secondary endpoints include pain measured with visual analogue scale, surgical time, reoperations, complications and radiological measurement of erosion in patients operated with hemiarthroplasty. Follow-up will be performed postoperatively after three months, 1, 2, 4 and 10 years. DISCUSSION: To our knowledge, this is the first randomized controlled trial comparing total hip arthroplasty and hemiarthroplasty for displaced femoral neck fracture in patients age 80 years and over. TRIAL REGISTRATION: Clinicaltrial.gov: NCT02246335.

Unstable hip arthroplasties. A prospective cohort study on seventy dislocating hips followed up for four years.

PURPOSE: Dislocating hip prosthesis remains a substantial clinical problem. The aim of this study is to describe the risk of recurrent instability after a primary dislocation of primary hip arthroplasty performed for osteoarthritis (OA) or femoral neck fracture (FNF). METHODS: Seventy patients (male/females: 25/45; mean age 77 [range 46-94]) with dislocating hip arthroplasties were included in a prospective cohort study and followed for four years. Radiographs and all surgical records were reviewed. We compared stable hips to those who either continued to dislocate or were revised due to recurrent instability (unstable group). RESULTS: Forty-two hips (60 %) had episodes of recurrent instability leading to repeated closed reductions or major revision surgery and were classified as unstable. A diagnosis of FNF and cognitive dysfunction (OR 9.3 [95 % CI 1.4-64.1]) or postoperative radiological discrepancies such as leg-lengthening and offset reduction increased the risk of further instability (OR 13.5 [95 % CI 1.3-148.1]). The surgical approach at primary surgery and ASA class did not significantly influence the risk of continued instability. CONCLUSIONS: Patients with a FNF and cognitive dysfunction or with sub-optimal postoperative radiographs after hip arthroplasty surgery are at high risk of recurrent instability after a primary dislocation. For hip fracture patients, all efforts should be made to avoid the first dislocation.

Porous titanium construct cup compared to porous coated titanium cup in total hip arthroplasty. A randomised controlled trial.

PURPOSE: The purpose of this study was to determine if a new titanium cup with increased porosity resulted in different periacetabular bone loss and migration compared to a porous coated cup. METHODS: Fifty-one patients with primary hip osteoarthritis were randomized to either a cup with porous titanium construct backside (porous titanium group, n = 25) or a conventional porous coated titanium cup (control group, n = 26). The primary outcome variable was change in periacetabular bone mineral density two years after surgery measured with dual energy X-ray absorptiometry (DXA). Secondary outcomes were implant fixation measured with radiostereometry (RSA) and clinical outcome scores. RESULTS: The pattern of bone remodelling was similar in the two groups with almost complete restoration to baseline values. BMD diminished in the two proximal zones and increased in the two distal zones. After minimal migration up to six months all implants in both groups became stable. We found no difference between the two groups in clinical outcome scores. CONCLUSIONS: In this prospective, randomized, controlled trial on a new porous titanium cup we found, compared to the control group, no clinically relevant differences regarding periacetabular bone preservation, implant fixation or clinical outcome up to two years postoperatively.

Vitamin-E diffused highly cross-linked polyethylene liner compared to standard liners in total hip arthroplasty. A randomized, controlled trial.

PURPOSE: We hypothesized that a vitamin E-treated polyethylene articulating liner had lower femoral head penetration than a conventional liner. METHODS: Fifty-one patients with primary hip osteoarthritis were randomized to an uncemented cup with either vitamin E-treated highly cross-linked polyethylene (HXLPE) (vitamin-e group, n = 25) or a standard HXLPE liner (control group, n = 26) and followed for two years after surgery. The outcome variable was polyethylene (PE) linear head penetration, measured with radiostereometry (RSA). RESULTS: The head penetration in x- (medial/lateral) and y- (vertical) axes was significantly lower for the vitamin E-treated liner up to two years with a mean difference between the groups of 0.10 mm (95 % CI 0.04-0.18) and 0.08 mm (95 % CI 0.01-0.15), respectively. The initial total penetration was lower for the vitamin-E group but did not reach statistical significance at two years with a mean difference between the groups of 0.07 mm (95 % CI -0.001 to 0.15, p = 0.09). We found no differences in clinical outcome between the groups. CONCLUSIONS: In this prospective, randomized, controlled trial on a new vitamin-E diffused HXLPE liner we found, compared to a conventional HXLPE liner, lower initial head penetration and lower superior and medial wear. A longer follow-up than two years is necessary to demonstrate lower overall head penetration in vitamin-E liners compared to contemporary highly cross-linked PE.

Lower periprosthetic bone loss and good fixation of an ultra-short stem compared to a conventional stem in uncemented total hip arthroplasty.

BACKGROUND AND PURPOSE: We hypothesized that an ultra-short stem would load the proximal femur in a more physiological way and could therefore reduce the adaptive periprosthetic bone loss known as stress shielding. PATIENTS AND METHODS: 51 patients with primary hip osteoarthritis were randomized to total hip arthroplasty (THA) with either an ultra-short stem or a conventional tapered stem. The primary endpoint was change in periprosthetic bone mineral density (BMD), measured with dual-energy x-ray absorptiometry (DXA), in Gruen zones 1 and 7, two years after surgery. Secondary endpoints were change in periprosthetic BMD in the entire periprosthetic region, i.e. Gruen zones 1 through 7, stem migration measured with radiostereometric analysis (RSA), and function measured with self-administered functional scores. RESULTS: The periprosthetic decrease in BMD was statistically significantly lower with the ultra-short stem. In Gruen zone 1, the mean difference was 18% (95% CI: -27% to -10%). In zone 7, the difference was 5% (CI: -12% to -3%) and for Gruen zones 1-7 the difference was also 5% (CI: -9% to -2%). During the first 6 weeks postoperatively, the ultra-short stems migrated 0.77 mm more on average than the conventional stems. 3 months after surgery, no further migration was seen. The functional scores improved during the study and were similar in the 2 groups. INTERPRETATION: Up to 2 years after total hip arthroplasty, compared to the conventional tapered stem the ultra-short uncemented anatomical stem induced lower periprosthetic bone loss and had equally excellent stem fixation and clinical outcome.

No effect of risedronate on femoral periprosthetic bone loss following total hip arthroplasty. A 4-year follow-up of 61 patients in a double-blind, randomized placebo-controlled trial.

BACKGROUND AND PURPOSE: We have previously shown that during the first 2 years after total hip arthroplasty (THA), periprosthetic bone resorption can be prevented by 6 months of risedronate therapy. This follow-up study investigated this effect at 4 years. PATIENTS AND METHODS: A single-center, double-blind, randomized placebo-controlled trial was carried out from 2006 to 2010 in 73 patients with osteoarthritis of the hip who were scheduled to undergo THA. The patients were randomly assigned to receive either 35 mg risedronate or placebo orally, once a week, for 6 months postoperatively. The primary outcome was the percentage change in bone mineral density (BMD) in Gruen zones 1 and 7 in the proximal part of the femur at follow-up. Secondary outcomes included migration of the femoral stem and clinical outcome scores. RESULTS: 61 of the 73 patients participated in this 4-year (3.9- to 4.1-year) follow-up study. BMD was similar in the risedronate group (n = 30) and the placebo group (n = 31). The mean difference was -1.8% in zone 1 and 0.5% in zone 7. Migration of the femoral stem, the clinical outcome, and the frequency of adverse events were similar in the 2 groups. INTERPRETATION: Although risedronate prevents periprosthetic bone loss postoperatively, a decrease in periprosthetic BMD accelerates when therapy is discontinued, and no effect is seen at 4 years. We do not recommend the use of risedronate following THA for osteoarthritis of the hip.

High risk of early periprosthetic fractures after primary hip arthroplasty in elderly patients using a cemented, tapered, polished stem.

BACKGROUND AND PURPOSE: Postoperative periprosthetic femoral fracture (PPF) after hip arthroplasty is associated with considerable morbidity and mortality. We assessed the incidence and characteristics of periprosthetic fractures in a consecutive cohort of elderly patients treated with a cemented, collarless, polished and tapered femoral stem (CPT). PATIENTS AND METHODS: In this single-center prospective cohort study, we included 1,403 hips in 1,357 patients (mean age 82 (range 52-102) years, 72% women) with primary osteoarthritis (OA) or a femoral neck fracture (FNF) as indication for surgery (367 hips and 1,036 hips, respectively). 64% of patients were ASA class 3 or 4. Hip-related complications and need for repeat surgery were assessed at a mean follow-up time of 4 (1-7) years. A Cox regression analysis was used to evaluate risk factors associated with PPF. RESULTS: 47 hips (3.3%) sustained a periprosthetic fracture at median 7 (2-79) months postoperatively; 41 were comminute Vancouver B2 or complex C-type fractures. The fracture rate was 3.8% for FNF patients and 2.2% for OA patients (hazard ratio (HR) = 4; 95% CI: 1.3-12). Patients > 80 years of age also had a higher risk of fracture (HR = 2; 95% CI: 1.1-4.5). INTERPRETATION: We found a high incidence of early PPF associated with the CPT stem in this old and frail patient group. A possible explanation may be that the polished tapered stem acts as a wedge, splitting the femur after a direct hip contusion. Our results should be confirmed in larger, registry-based studies, but we advise caution when using this stem for this particular patient group.

Measurement of the migration of a focal knee resurfacing implant with radiostereometry.

BACKGROUND AND PURPOSE: Articular resurfacing metal implants have been developed to treat full-thickness localized articular cartilage defects. Evaluation of the fixation of these devices is mandatory. Standard radiostereometry (RSA) is a validated method for evaluation of prosthetic migration, but it requires that tantalum beads are inserted into the implant. For technical reasons, this is not possible for focal articular resurfacing components. In this study, we therefore modified the tip of an articular knee implant and used it as a marker for RSA, and then validated the method. MATERIAL AND METHODS: We modified the tip of a resurfacing component into a hemisphere with a radius of 3 mm, marked it with a 1.0-mm tantalum marker, and implanted it into a sawbone marked with 6 tantalum beads. Point-motion RSA of the "hemisphere bead" using standard automated RSA as the gold standard was compared to manual measurement of the tip hemisphere. 20 repeated stereograms with gradual shifts of position of the specimen between each double exposure were used for the analysis. The tip motion was compared to the point motion of the hemisphere bead to determine the accuracy and precision. RESULTS: The accuracy of the manual tip hemisphere method was 0.08-0.19 mm and the precision ranged from 0.12 mm to 0.33 mm. INTERPRETATION: The accuracy and precision for translations is acceptable when using a small hemisphere at the tip of a focal articular knee resurfacing implant instead of tantalum marker beads. Rotations of the implant cannot be evaluated. The method is accurate and precise enough to allow detection of relevant migration, and it will be used for future clinical trials with the new implant.

Good stability but high periprosthetic bone mineral loss and late-occurring periprosthetic fractures with use of uncemented tapered femoral stems in patients with a femoral neck fracture.

BACKGROUND AND PURPOSE: We previously evaluated a new uncemented femoral stem designed for elderly patients with a femoral neck fracture and found stable implant fixation and good clinical results up to 2 years postoperatively, despite substantial periprosthetic bone mineral loss. We now present the medium-term follow-up results from this study. PATIENTS AND METHODS: In this observational prospective cohort study, we included 50 patients (mean age 81 (70-92) years) with a femoral neck fracture. All patients underwent surgery with a cemented cup and an uncemented stem specifically designed for fracture treatment. Outcome variables were migration of the stem measured with radiostereometry (RSA) and periprosthetic change in bone mineral density (BMD), measured with dual-energy X-ray absorptiometry (DXA). Hip function and health-related quality of life were assessed using the Harris hip score (HHS) and the EuroQol-5D (EQ-5D). DXA and RSA data were collected at regular intervals up to 4 years, and data concerning reoperations and hip-related complications were collected during a mean follow-up time of 5 (0.2-7.5) years. RESULTS: At 5 years, 19 patients had either passed away or were unavailable for further participation and 31 could be followed up. Of the original 50 patients, 6 patients had suffered a periprosthetic fracture, all of them sustained after the 2-year follow-up. In 19 patients, we obtained complete RSA and DXA data and no component had migrated after the 2-year follow-up. We also found a continuous total periprosthetic bone loss amounting to a median of -19% (-39 to 2). No changes in HHS or EQ-5D were observed during the follow-up period. INTERPRETATION: In this medium-term follow-up, the stem remained firmly fixed in bone despite considerable periprosthetic bone mineral loss. However, this bone loss might explain the high number of late-occurring periprosthetic fractures. Based on these results, we would not recommend uncemented femoral stems for the treatment of femoral neck fractures in the elderly.

Ureaplasma urealyticum infection in total hip arthroplasty leading to revision.

We describe an infection with Ureaplasma urealyticum causing rapid loosening of a cemented total hip arthroplasty. When reviewing the literature we found that no such case has been reported previously. Taking intraoperative cultures for U urealyticum during revision surgery is not a standard procedure. In cases with rapid, presumed aseptic, loosening of a total hip arthroplasty, an infection with U urealyticum should be considered.

Identification of adverse events at an orthopedics department in Sweden.

BACKGROUND AND PURPOSE: Adverse events (AEs) are common in acute care hospitals, but there have been few data concerning AEs in orthopedic patients. We tested and evaluated a patient safety model (the Wimmera clinical risk management model) and performed a three-stage retrospective review of records to determine the occurrence of AEs in adult orthopedic inpatients. METHODS: The computerized medical and nursing records of 395 patients were included and screened for AEs using 12 criteria. Positive records were then reviewed by two senior orthopedic surgeons using a standardized protocol. An AE had to have occurred during the index admission or within the first 28 days of discharge from the Orthopedics Department. Screening of additional systems for reporting of AEs was also carried out for the same period. The number of patients suffering an AE and the number of AEs were recorded. RESULTS: Altogether, 60 (15 %) of 395 patients checked in the screening of records experienced 65 AEs (16%) due to healthcare management. Of the 65 AEs, 34 were estimated to have a high degree of preventability. 47 of the 65 AEs occurred during the index admission and 18 within 28 days of discharge. In screening of local and nationwide reporting systems for the same patients, 4 additional AEs were identified-2 of which were previously unknown. 67 different AEs were detected by using the Wimmera model (17%) INTERPRETATION: Using the Wimmera model with manual screening and review of records, many more AEs were detected than in all other traditional local and nationwide reporting systems used in Sweden when screening was done for the same period.

Waiting time to surgery is correlated with an increased risk of serious adverse events during hospital stay in patients with hip-fracture: A cohort study.

BACKGROUND: Hip fractures are common in the elderly and are associated with a high adverse event and mortality rate. Time to surgery is one of the major modifiable risk factors influencing adverse outcomes in hip-fracture patients. National guidelines and recommendations have been introduced which advocate specific time frames in which surgery should be performed i.e. within 24-48h. These time constraints have been arbitrarily set without being modelled on the linear assumption i.e. that risk increases continually over time and not within specific cut-off times. OBJECTIVES: To investigate how waiting time to surgery influenced the risk of serious adverse events in hip-fracture patients during the hospital stay and to examine how the risk increased over time. DESIGN: An observational single cohort study Participants 576 patients (72.4% females, mean [SD] age 82 [10]) years, with a hip fracture were included in the cohort study. METHODS: The outcomes of the study were the occurrence of serious adverse events during hospital stay, length of stay and one-year mortality. A structured medical record review was carried out to identify outcomes and mortality data was obtained from the Swedish National Death Registry. Waiting time to surgery was used as the exposure variable and age, sex, type of fracture, comorbidities using the American Society of Anaesthesiologists classification score and the presence of cognitive dysfunction were identified as confounders. A logistic regression analysis was performed to identify risk factors influencing outcomes. RESULTS: A total of 119 patients (20.6%) suffered 397 (range 1-5) serious adverse events during hospital stay. Every 10h of waiting time to surgery increased the risk of serious adverse events by 12% (odds ratio 1.12 [95% confidence interval 1.02-1.23]). We found no optimal cut-off times for waiting time to surgery. For every 24h of waiting time, the length of stay from surgery was increased by 0.6days (95% CI 0.1-1.1). We found no correlation between waiting time to surgery and one-year mortality. CONCLUSIONS: A large proportion of patients suffered from at least one serious adverse event after hip-fracture surgery and there are no safe limits for waiting time to surgery for hip-fracture patients. As the risk increases with every hour of waiting time, patients with higher American Society of Anesthesiologists classification scores, males and those with subtrochanteric fractures should be prioritized for surgery.

Migration and head penetration of Vitamin-E diffused cemented polyethylene cup compared to standard cemented cup in total hip arthroplasty: study protocol for a randomised, double-blind, controlled trial (E1 HIP).

INTRODUCTION: In vitro, Vitamin-E-diffused, highly cross-linked polyethylene (PE) has been shown to have superior wear resistance and improved mechanical properties when compared to those of standard highly cross-linked PE liners used in total hip arthroplasty (THA). The aim of the study is to evaluate the safety of a new cemented acetabular cup with Vitamin-E-doped PE regarding migration, head penetration and clinical results. METHODS AND ANALYSIS: In this single-centre, double-blinded, randomised controlled trial, we will include 50 patients with primary hip osteoarthritis scheduled for THA and randomise them in a 1:1 ratio to a cemented cup with either argon gas-sterilised PE (control group) or Vitamin-E-diffused PE (vitamin-e group). All patients and the assessor of the primary outcome will be blinded and the same uncemented stem will be used for all participants. The primary end point will be proximal migration of the cup at 2 years after surgery measured with radiostereometry. Secondary end points include proximal migration at other follow-ups, total migration, femoral head penetration, clinical outcome scores and hip-related complications. Patients will be followed up at 3 months and at 1, 2, 5 and 10 years postoperatively. RESULTS: Results will be analysed using 95% CIs for the effect size. A regression model will also be used to adjust for stratification factors. ETHICS AND DISSEMINATION: The ethical committee at Karolinska Institutet has approved the study. The first results from the study will be disseminated to the medical community via presentations and publications in relevant medical journals when the last patient included has been followed up for 2 years. TRIAL REGISTRATION NUMBER: NCT02254980.

Larger femoral periprosthetic bone mineral density decrease following total hip arthroplasty for femoral neck fracture than for osteoarthritis: a prospective, observational cohort study.

Studies on patients with degenerative joint disease of the hip show that femoral periprosthetic bone mineral decreases following total hip arthroplasty. Scarcely any osteodensitometric data exist on femoral neck fracture (FNF) patients and periprosthetic bone remodelling. In two parallel cohorts we enrolled 87 patients (mean age, 72 ± 12 years; male:female ratio, 30:57) undergoing total hip arthroplasty for either primary osteoarthritis (OA) of the hip (n = 37) or for an acute FNF (n = 50) and followed them for a mean of 5.4 years. Outcomes were bone mineral density (BMD) changes in the periprosthetic Gruen zones 1-7, the incidence of periprosthetic fractures and clinical outcome. The bone mineral loss in the fracture group was more than twice that of the osteoarthritis group, -16.9% versus -6.8% (p = 0.004). The incidence of periprosthetic fractures was 12% (6/50) in the fracture cohort compared with none (0%) in the OA cohort (p = 0.03). Periprosthetic bone mineral loss following total hip arthroplasty is significantly greater in patients who are treated for acute FNF than in OA patients. This decrease of BMD follows a different pattern with the FNF patients losing larger proportions of bone in Gruen zones 1, 2, 6, and 7 while the OA patients tend to have larger losses only in zones 1 and 7.

Gross osteolytic tibia tunnel widening with the use of Gore-Tex anterior cruciate ligament prosthesis: a radiological, arthrometric and clinical evaluation of 17 patients 13-15 years after surgery.

BACKGROUND: Postoperative widening of the bone tunnels have been found after anterior cruciate ligament reconstruction using autologus bone-patellar tendon-bone or hamstring tendon grafts. These changes seem to be of no clinical significance in a short to midterm follow-up. We investigated if a synthetic graft evokes the same bone tunnel widening and if it is of clinical significance in a longterm follow-up. METHODS: We examined 17 patients, 13-15 years after their anterior cruciate ligament reconstruction using a Gore-Tex ligament prosthesis. The follow-up consisted of clinical examination, K-1000 arthrometric measurement, Tegner, Lysholm and IKDC scores, and CT examination of their tibia bone tunnels. 6 patients had been reoperated before follow-up, 3 because of graft rupture and 3 because of effusion and/or pain. RESULTS: 5 patients were graded as normal (n = 2) or nearly normal according to the IKDC score, and 4 of these patients still had their Gore-Tex prosthesis intact. 15 of the patients had a tibia bone tunnel wider than the drilled 7.9 mm diameter, ranging from 9.6 to 26 mm. These changes in the bone tunnels were in some cases without symptoms and could not be detected with arthroscopy, clinical examination, arthrometry or evaluation scores. We do not know whether they are progressive. INTERPRETATION: Based on our findings, we recommend that patients who have had a Gore-Tex anterior cruciate ligament reconstruction should be examined not only clinically or by questionnaire, but also with CT.

Reconstruction of acute anterior cruciate ligament injuries: a prospective, randomised study of 40 patients with 7-year follow-up. No advantage of synthetic augmentation compared to a traditional patellar tendon graft.

BACKGROUND: In a prospective, randomised study, we compared the results of anterior cruciate ligament reconstruction using the conventional medial patellar tendon strip procedure with the Kennedy ligament augmentation device (LAD) over-the-top augmentation technique. The aim of the study was to see if the addition of this device, with its specific potential complications (infection, synovitis, mechanical failure) and increased costs, gave better functional stability and less donor site morbidity. METHODS: Forty patients ( n=20+20) with high physical demands, anterior cruciate ligament rupture less than 3 weeks old, and positive Lachman and pivot shift tests were included in the study. They were randomised by instructions in a sealed envelope that was randomly chosen. Postoperatively, they were immobilised in a plaster of Paris cast for 2 weeks. Full weight-bearing was not allowed until 6 weeks after the operation. Strength training on the operated side started when movement was restored to nearly normal, usually after 8-10 weeks. Return to full sport activity was allowed 1 year after the operation. Clinical and arthrometric follow-up was performed yearly using the Lysholm functional score, Tegner activity score, KT-1000 testing, Lachman and pivot shift tests. Follow-up lasted 3-9 years (mean 7 years). RESULTS AND CONCLUSIONS: At last follow-up we found no statistical difference in stability tests, functional or activity scores; both groups showed stable improvement concerning scores and arthrometry compared with the preoperative values. No advantages were associated with the use of the Kennedy LAD, and we do not recommend it or a similar device for uncomplicated cases. New augmentation devices are simply launched onto the market, and we recommend caution and thorough evaluation in prospective, randomised studies before they are adopted into use.