Smoking has been associated with poor tissue oxygenation and vascularisation, predisposing smokers to a higher risk for postsurgical infections. The aim of this study was to estimate and compare the incidence of prosthetic joint infection (PJI) following primary total joint arthroplasty (TJA) according to smoking status. A prospective hospital-registry based cohort was used including all primary total knee and hip arthroplasties performed between 03/1996 and 12/2013 and following them until 06/2014. Smoking status at time of surgery was classified in never, former and current smoker. Incidence rates and incidence rate ratios (IRR) for PJI according to smoking status were assessed within the first year and over the whole study period. Adjusted IRRs were obtained using cox regression model. Adjustment was performed for the following baseline characteristics: age, sex, BMI, ASA score, diabetes, arthroplasty site (knee or hip) and surgery duration.Background
Methods
Large-head metal-on-metal (MoM) total hip replacements
(THR) have given rise to concern. Comparative studies of small-head
MoM THRs over a longer follow-up period are lacking. Our objective
was to compare the incidence of complications such as infection,
dislocation, revision, adverse local tissue reactions, mortality
and radiological and clinical outcomes in small-head (28 mm) MoM
and ceramic-on-polyethylene (CoP) THRs up to 12 years post-operatively. A prospective cohort study included 3341 THRs in 2714 patients.
The mean age was 69.1 years (range 24 to 98) and 1848 (55.3%) were
performed in women, with a mean follow-up of 115 months (18 to 201).
There were 883 MoM and 2458 CoP bearings. Crude incidence rates
(cases/1000 person-years) were: infection 1.3 In conclusion, we found similar results for small-head MoM and
CoP bearings up to ten years post-operatively, but after ten years
MoM THRs had a higher risk of all-cause revision. Furthermore, the
presence of an adverse response to metal debris seen in the small-head
MOM group at revision is a cause for concern. Cite this article:
The maintenance of quality and integrity in clinical
and basic science research depends upon peer review. This process
has stood the test of time and has evolved to meet increasing work
loads, and ways of detecting fraud in the scientific community.
However, in the 21st century, the emphasis on evidence-based medicine
and good science has placed pressure on the ways in which the peer
review system is used by most journals. This paper reviews the peer review system and the problems it
faces in the digital age, and proposes possible solutions. Cite this article:
Whether patients with asymptomatic bacteriuria
should be investigated and treated before elective hip and knee replacement
is controversial, although it is a widespread practice. We conducted
a prospective observational cohort study with urine analyses before
surgery and three days post-operatively. Patients with symptomatic
urinary infections or an indwelling catheter were excluded. Post-discharge
surveillance included questionnaires to patients and general practitioners
at three months. Among 510 patients (309 women and 201 men), with
a median age of 69 years (16 to 97) undergoing lower limb joint
replacements (290 hips and 220 knees), 182 (36%) had pre-operative asymptomatic
bacteriuria, mostly due to We conclude that testing and treating asymptomatic urinary tract
colonisation before joint replacement is unnecessary. Cite this article:
Conventional pre-operative planning for total hip arthroplasty mostly relies on the patient radiologic anatomy for the positioning and choice of implants. This kind of planning essentially remains a static approach since dynamic aspects such as the joint kinematics are not taken into account. Hence, clinicians are not able to fully consider the evolving behavior of the prosthetic joint that may lead to implant failures. In fact, kinematics plays an important role since some movement may create conflicts within the prosthetic joint and even provoke dislocations. The goal of our study was to assess the relationship between acetabular implant positioning variations and resultant impingements and loss of joint congruence during daily activities. In order to obtain accurate hip joint kinematics for simulation, we performed an in-vivo study using optical motion capture and magnetic resonance imaging (MRI). Motion capture and MRI was carried out on 4 healthy volunteers (mean age, 28 years). Motion from the subjects was acquired during routine (stand-to-sit, lie down) and specific activities (lace the shoes while seated, pick an object on the floor while seated or standing) known to be prone to implant dislocation and impingement. The hip joint kinematics was computed from the recorded markers trajectories using a validated optimized fitting algorithm (accuracy: translational error ≍ 0.5 mm, rotational error < 3°) which accounted for skin motion artifactsand patient-specific anatomical constraints (e.g. bone geometry reconstructed from MRI, hip joint center) (Fig. 1). 3D models of prosthetic hip joints (pelvis, proximal femur, cup, stem, head) were developed based on variations of acetabular cup's inclination (40°, 45°, 60°) and anteversion (0°, 15°, 30°) parameters, resulting in a total of 9 different implant configurations. Femoral anteversion remained fixed and determined as “neutral” with the stem being parallel to the posterior cortex of the femoral neck. Motion capture data of daily tasks were applied to all implant configurations. While visualizing the prosthetic models in motion, a collision detection algorithm was used to locate abnormal contacts between both bony and prosthetic components (Fig. 2). Moreover, femoral head translations (subluxation) were computed to evaluate the joint congruence.Introduction
Methods
Today, there is no clear consensus as to the amplitude of movement of the “normal hip”. Knowing the necessary joint mobility for everyday life is important to understand different pathologies and to better plan their treatments. Moreover, determining the hip range of motion (ROM) is one of the key points of its clinical examination. Unfortunately this process may lack precision because of movement of other joints around the pelvis. Our goal was to perform a preliminary study based on the coupling of MRI and optical motion capture to define precisely the necessary hip joint mobility for everyday tasks and to assess the accuracy of the hip ROM clinical exam. MRI was carried out on 4 healthy volunteers (mean age, 28 years). A morphological analysis was performed to assess any bony abnormalities. Two motion capture sessions were conducted: one aimed at recording routine activities (stand-to-sit, lie down, lace the shoes while seated, pick an object on the floor while seated or standing) known to be painful or prone to implant failures. During the second session, a hip clinical exam was performed successively by 2 orthopedists (2 and 12 years' experience), while the motion of the subjects was simultaneously recorded (Fig.1). These sequences were captured: 1) supine: maximal flexion, maximal IR/ER with hip flexed 90°, maximal abduction; 2) seated: maximal IR/ER with hip and knee flexed 90°. A hand held goniometer was used by clinicians to measure hip angles in those different positions. Hip joint kinematics was computed from the markers trajectories using a validated optimized fitting algorithm which accounted for skin motion artifacts (accuracy: translational error≍0.5 mm, rotational error <3°). The resulting computed motions were applied to patient-specific hip joint 3D models reconstructed from their MRI data (Fig. 2). Hip angles were determined at each point of the motion thanks to two bone coordinate systems (pelvis and femur). The orthopedist's results were compared.Introduction
Methods
We undertook a retrospective case-control study
to assess the clinical variables associated with infections in open fractures.
A total of 1492 open fractures were retrieved; these were Gustilo
and Anderson grade I in 663 (44.4%), grade II in 370 (24.8%), grade
III in 310 (20.8%) and unclassifiable in 149 (10.0%). The median
duration of prophylaxis was three days (interquartile range (IQR)
1 to 3), and the median number of surgical interventions was two
(1 to 9). We identified 54 infections (3.6%) occurring at a median
of ten days (IQR 5 to 20) after trauma. Pathogens intrinsically
resistant to the empirical antibiotic regimen used (enterococci, Infection in open fractures is related to the extent of tissue
damage but not to the duration of prophylactic antibiotic therapy.
Even for grade III fractures, a one-day course of prophylactic antibiotics
might be as effective as prolonged prophylaxis. Cite this article:
There are no recent studies comparing cable with
wire for the fixation of osteotomies or fractures in total hip replacement
(THR). Our objective was to evaluate the five-year clinical and
radiological outcomes and complication rates of the two techniques.
We undertook a review including all primary and revision THRs performed
in one hospital between 1996 and 2005 using cable or wire fixation.
Clinical and radiological evaluation was performed five years post-operatively.
Cables were used in 51 THRs and wires in 126, and of these, 36 THRs
with cable (71%) and 101 with wire (80%) were evaluated at follow-up.
The five-year radiographs available for 33 cable and 91 wire THRs
revealed rates of breakage of fixation of 12 of 33 (36%) and 42
of 91 (46%), respectively. With cable there was a significantly
higher risk of metal debris (68% In conclusion, we found a higher incidence of complications and
a trend towards increased infection and foreign-body reaction with
the use of cables.
In foot and ankle surgery incorrect placement of implants, or inaccuracy in fracture reduction may remain undiscovered with the use of conventional C-arm fluoroscopy. These imperfections are often only recognized on postoperative computer tomography scans. The apparition of three dimensional (3D) mobile Imaging system has allowed to provide an intraoperative control of fracture reduction and implant placement. Three dimensional computer assisted surgery (CAS) has proven to improve accuracy in spine and pelvic surgery. We hypothesized that 3D-based CAS could improve accuracy in foot and ankle surgery. The purpose of our study was to evaluate the feasibility and utility of a multi-dimensional surgical imaging platform with intra-operative three dimensional imaging and/or CAS in a broad array of foot and ankle traumatic and orthopaedic surgery. Cohort study of patients where the 3D mobile imaging system was used for intraoperative 3D imaging or 3D-based CAS in foot and ankle surgery. The imaging system used was the O-arm Surgical Imaging System and the navigation system was the Medtronic's StealthStation. Surgical procedures were performed according to standard protocols. In case of fractures, image acquisition was performed after reduction of the fracture. In cases of 3D-based CAS, image acquisition was performed at the surgical step before implants placement. At the end of the operations, an intraoperative 3D scan was made. We used the O-arm Surgical Imaging system in 11 patients: intraoperative 3D scans were performed in 3 cases of percutaneus fixation of distal tibio-fibular syndesmotic disruptions; in 2 of the cases, revision of reduction and/or implant placement were needed after the intraoperative 3D scan. Three dimensional CAS was used in 10 cases: 2 open reduction and internal fixation (ORIF) of the calcaneum, 1 subtalar fusion, 2 ankle arthrodesis, 1 retrograde drilling of an osteochondral lesion of the talus, 1 Charcot diabetic reconstruction foot and 1 intramedullary screw fixation of a fifth metatarsal fracture. The guidance was used essentially for screw placement, except in the retrograde drilling of an osteochondral lesion where the guidance was used to navigate the drill tool. Intraoperative 3D imaging showed a good accuracy in implant placement with no need to revision of implants. We report a preliminary case series with use of the O-arm Surgical Imaging System in the field of foot and ankle surgery. This system has been used either as intraoperative 3D imaging control or for 3D-based CAS. In our series, the 3D computer assisted navigation has been very useful in the placement of implants and has shown that guidance of implants is feasible in foot and ankle surgery. Intraoperative 3D imaging could confirm the accuracy of the system as no revisions were needed. Using the O-arm as intraoperative 3D imaging was also beneficial because it allowed todemonstrate intraoperative malreduction or malposition of implants (which were repositioned immediately). Intraoperative 3D imaging system showed very promising preliminary results in foot and ankle surgery. There is no doubt that intraoperative use of 3D imaging will become a standard of care. The exact indications need however to be defined with further studies.
Currently, a validate scale of ankle osteoarthritis (OA) is not available and different classifications have been used, making comparisons between studies difficult. In other joints as the hip and knee, the Kellgren-Lawrence (K&L) scale, chosen as reference by the World Health Organizations is widely used to characterize OA. It consists of a physician based assessment of 3 radiological features: osteophyte formation, joint space narrowing and bone end sclerosis described as follows: grade 0: normal joint; grade 1: minute osteophytes of doubtfull significance; grade 2: definite osteophytes; grade 3: moderate diminution of joint space; grade 4: joint space greatly impaired, subchondral sclerosis. Until now, the K&L scale has never been validated in the ankle. Our objective was to assess the usefulness of the K&L scale for the ankle joint, by determining its reliability and by comparing it to functional scores and to computerized minimal joint space width (minJSW) and sclerosis measurements. Additionally we propose an atlas of standardized radiographs for each of the K&L grades in the ankle. 73 patients 10 to 20 years post ankle ORIF were examined. Bilateral ankle radiographs were taken. Four physicians independently assessed the K&L grades and evaluated tibial and talar sclerosis on anteroposterior radiographs. Functional outcome was assessed with the AOFAS Hindfoot score. Bone density and minJSW were measured using a previously validated Ankle Image Digital Analysis software (AIDA).Introduction
Methods
Among patients with ankle osteoarthritis (OA) a post-traumatic origin is much more frequent than among those with knee or hip OA. However, long-term studies evaluating risk factors for the development of OA after ankle fractures are lacking. Retrospective cohort study including consecutive patients operated at our institution between 1/1988 and 12/1997 for malleolar fractures treated with open-reduction and internal fixation (ORIF). Ankle OA was independently assessed by two reviewers on standardized radiographs using the Kellgren and Lawrence (K&L) scale. Multivariate logistic regression analysis was performed to determine predictors for OA.Introduction
Methods
A recent review of the literature on metal-on-metal total hip arthroplasties (THA) revealed the lack of comparative clinical studies with a sufficient sample size and the inclusion of patient-reported outcomes as well as patient activity levels. We conducted a prospective cohort study including all metal-on-metal and conventional polyethylene (PE)-ceramic THAs with an uncemented cup (Morscher press-fit cup), a 28mm head and operated upon via a lateral approach at our University hospital between 1/1999 and 12/2008. Only THAs for primary osteoarthritis were included. The study population is part of the Geneva Hip Arthroplasty Registry, a prospective cohort followed since 1996. The following outcomes were compared between the two groups (metal-on-metal=group 1 vs. PE-ceramic bearing=group 2): (1) Complication rates with respect to infection, dislocation and revision, (2) Radiographic outcomes (presence of linear or focal femoral osteolysis, loosening), and (3) Clinical outcomes (Harris Hip score increase, SF-12, activity and patient satisfaction evaluation, presence of groin pain). Patients operated between 1/1999 and 12/2004 were evaluated five years postoperatively by an independent assessor. Cox regression analysis was used to compare incidence rates while adjusting for differences in baseline characteristics.Introduction
Methods
Large diameter metal on metal cups have been used in total hip arthroplasty advocating superior results with respect to dislocation rates, range of motion and long term survival. The Durom cup used as part of the Durom hip resurfacing system has been incriminated with poor short term results sometimes correlated to incorrect positioning of either the femoral or acetabular component. Our objective was to evaluate short term results of the Durom cup used in conjunction with standard stems. We prospectively followed all patients with a large diameter metal-on-metal articulation (Durom) and a standard stem operated upon between 9/2004 and 9/2008. Patients were seen at follow-up for a clinical (Harris hip score=HHS, UCLA scale and patient satisfaction), radiographic and questionnaire assessment.Introduction
Methods
Orthopaedic surgeons are frequently asked to perform a revision total hip arthroplasty (THA) in patients over 80 years of age. Our objective was to evaluate the outcomes after revision THA in patients 80 years or older and compare them to a cohort of patients less than 80 years of age. We reviewed all revision THAs performed in our institution from 3/1996 to 12/2008. We compared intra- and post-operative complications (medical and orthopaedic), mortality, clinical outcomes and patient satisfaction between the two age groups. Peri-operative information and complications were collected prospectively, and clinical outcome data were obtained both pro- and retrospectively. The Merle d'Aubigné score, Harris Hip score, general health (SF-12) and patient satisfaction (visual analog scale) were assessed.Introduction
Methods
We conducted a longitudinal study including patients with the same type of primary hybrid total hip replacement and evaluated patient activity and femoral osteolysis at either five or ten years post-operatively. Activity was measured using the University of California, Los Angeles scale. The primary outcome was the radiological assessment of femoral osteolysis. Secondary outcomes were revision of the femoral component for aseptic loosening and the patients’ quality of life. Of 503 hip replacements in 433 patients with a mean age of 67.7 years (30 to 91), 241 (48%) were seen at five and 262 (52%) at ten years post-operatively. Osteolytic lesions were identified in nine of 166 total hip replacements (5.4%) in patients with low activity, 21 of 279 (7.5%) with moderate activity, and 14 of 58 (24.1%) patients with high activity. The risk of osteolysis increased with participation in a greater number of sporting activities. In multivariate logistic regression adjusting for age, gender, body mass index and the inclination angle of the acetabular component, the adjusted odds ratio for osteolysis comparing high In conclusion, of patients engaged in high activity, 24% had developed femoral osteolysis five to ten years post-operatively.
None of the patients required cup revision for aseptic loosening. Complications included 12 dislocations and 3 deep infections resulting in 2 total revisions. In 3 patients the stem was revised for aseptic loosening at a mean of 63 months. At 10-years the survivorship was 98.6% (95% CI 96.7; 99.4) with endpoint revision for any cause. Mean total wear was 0.89 mm (±0.5). 32 cups (18.8%) with a cup inclination >
45° had a mean wear of 1.06 mm (±0.5), whereas 138 cups (81.2%) with inclination <
45° had a mean wear of 0.86 mm (±0.5), p=0.036. In 16 cases osteolytic defects around the stem were present. The outcome scores at 10 years were: HHS 85.9 (±14.1), WOMAC pain 70.7 (±24.7), WOMAC function 68.8 (±24.5), SF-12 physical score 40.3 (±9.2) and mental score 47.0 (±10.4). Ninety-four percent of the patients were satisfied or very satisfied.