We evaluated a large database with mechanical failure of a single uncemented modular femoral component, used in revision hip arthroplasty, as the end point and compared them to a control group treated with the same implant. Patient- and implant-specific risk factors for implant failure were analyzed. All cases of a fractured uncemented modular revision femoral component from one manufacturer until April 2017 were identified and the total number of implants sold until April 2017 was used to calculate the fracture rate. The manufacturer provided data on patient demographics, time to failure, and implant details for all notified fractured devices. Patient- and implant-specific risk factors were evaluated using a logistic regression model with multiple imputations and compared to data from a previously published reference group, where no fractures had been observed. The results of a retrieval analysis of the fractured implants, performed by the manufacturer, were available for evaluation.Aims
Methods
There is little information regarding the risk of a patient developing prosthetic joint infection (PJI) after primary total knee arthroplasty (TKA) when the patient has previously experienced PJI of a TKA or total hip arthroplasty (THA) in another joint. The goal of this study was to compare the risk of PJI of primary TKA in this patient population against matched controls. We retrospectively reviewed 95 patients (102 primary TKAs) treated between 2000 and 2014 with a history of PJI in another TKA or THA. A total of 50 patients (53%) were female. Mean age was 69 years (45 to 88) with a mean body mass index (BMI) of 36 kg/m2 (22 to 59). In total, 27% of patients were on chronic antibiotic suppression. Mean follow-up was six years (2 to 16). We 1:3 matched these (for age, sex, BMI, and surgical year) to 306 primary TKAs performed in 306 patients with a THA or TKA of another joint without a subsequent PJI. Competing risk with death was used for statistical analysis. Multivariate analysis was followed to evaluate risk factors for PJI in the study cohort.Aims
Patients and Methods
The aims of this study were to characterize antibiotic choices for perioperative total knee arthroplasty (TKA) and total hip arthroplasty (THA) prophylaxis, assess antibiotic allergy testing efficacy, and determine rates of prosthetic joint infection (PJI) based on perioperative antibiotic regimen. We evaluated all patients undergoing primary TKA or THA at a single academic institution between January 2004 and May 2017, yielding 29 695 arthroplasties (22 705 patients), with 3411 arthroplasties in 2576 patients (11.5%) having undergone preoperative allergy testing. A series of institutional databases were combined to identify allergy consultation outcomes, perioperative antibiotic regimen, and infection-free survivorship until final follow-up.Aims
Patients and Methods
Platelet-rich plasma (PRP) is being used increasingly often in the clinical setting to treat tendon-related pathologies. Yet the optimal PRP preparations to promote tendon healing in different patient populations are poorly defined. Here, we sought to determine whether increasing the concentration of platelet-derived proteins within a derivative of PRP, platelet lysate (PL), enhances tenocyte proliferation and migration Concentrated PLs from both young (< 50 years) and aged (> 50 years) donors were prepared by exposing pooled PRP to a series of freeze-thaw cycles followed by dilution in plasma, and the levels of several platelet-derived proteins were measured using multiplex immunoassay technology. Human tenocytes were cultured with PLs to simulate a clinically relevant PRP treatment range, and cell growth and migration were assessed using DNA quantitation and gap closure assays, respectively.Objectives
Methods
First generation cephalosporins remain the gold standard perioperative antibiotic for total hip and knee arthroplasty (THA, TKA). However, some patients have documented or self-reported allergies to antibiotics, most commonly penicillin, that result in changes to perioperative antibiotic coverage. Furthermore, patients testing positive for methicillin resistant staphylococcus aureus (MRSA) represent another group where an alternative to cefazolin, typically vancomycin, is often chosen for perioperative prophylaxis. The aims of this study were to 1) characterize the antibiotic choices for perioperative prophylaxis at the time of primary TKA and THA, 2) assess the efficacy of a preoperative antibiotic allergy testing program, and 3) determine rates of periprosthetic joint infection (PJI) based on perioperative antibiotic regimen. We evaluated all patients undergoing primary TKA or THA at a single academic institution from January 2004-May 2017, yielding a cohort of 29,695 patients. A series of institutional databases were combined to determine which patients underwent antibiotic allergy testing prior to surgery, outcomes from the allergy consultation, perioperative antibiotic management strategy, and survivorship free of infection until final follow-up.Introduction
Methods
There is no literature regarding the risk of a patient developing PJI after primary TKA if the patient has previously experienced PJI of a TKA or THA in another joint. The goal of this study was to compare the risk of PJI of primary TKA in this patient population compared to matched controls. We retrospectively reviewed 95 patients (102 primary TKAs) from 2000–2014 with a history of a TKA or THA PJI in another joint. Mean age was 69 years; mean BMI was 36 kg/m2. 27% high-risk patients were on chronic antibiotic suppression. Mean follow-up was 6 years. We 1:3 matched (to age, sex, BMI, and surgical year) these to 306 primary TKAs performed in patients with a THA or TKA of another joint without a subsequent PJI. Competing risk with death was used for statistical analysis. Multivariate analysis was utilized to evaluate risk factors for PJI in the study cohort.Introduction
Methods
Two-stage revision surgery remains the gold standard as treatment for periprosthetic hip infections. The purpose of this study was to determine the rate of infection eradication after two-stage revision hip arthroplasty in patients treated with intraoperatively surgeon-molded articulating spacers as well as to foreshadow the future economical impact of these articulating antibiotic spacers to those commercially available. Thirty-five patients who underwent two-stage revision hip arthroplasty due to chronic periprosthetic infection between 2003–2014 were followed clinically and radiographically an average of 4.9 years postoperatively [2.2–9.2]. 17 male and 18 female patients with a mean age of 62 [34–82] had articulating spacers, made in the operating room, inserted at the first stage. [The overall expense of the custom-made antibiotic spacers and the commercially available spacers was calculated and compared using a student t test.]Introduction
Methods
Using 90% of final height as a benchmark, we sought to develop
a quick, quantitative and reproducible method of estimating skeletal
maturity based on topographical changes in the distal femoral physis. Serial radiographs of the distal femoral physis three years prior
to, during, and two years following the chronological age associated
with 90% of final height were analyzed in 81 healthy children. The
distance from the tip of the central peak of the distal femoral
physis to a line drawn across the physis was normalized to the physeal width.Aims
Patients and Methods
A longitudinal study was done assessing the latest radiographs available in a series of collarless Corail uncemented stems which have reported survival rates of 95% at 20 years. Parameters scored included the degree of “Ghosting” or delamination, the Gruen, the stem fit in the femoral canal and the degree of calcar resorption. Patient and implant demographics were noted. At 3 years the loosening rate was 23% reaching 64% at 6 years after the index procedure. It was present in all age groups, with a peak in the 24 to 49 year age group. Males and females had the same occurrence. When it was present this was always in zone 1. It was present in 6% of patients in zone 7, but then always associated with zone 1 changes. High and standard off-set stems had the same loosening rates. The looser fit of the stem the higher the incidence of loosening. There was no correlation to the type of bearing surface or the degree of calcar resorption. Those patients with a BMI of 25 – 35 had lower loosening rates compared to those with higher or lower BMI's. We postulate that cancellous bone on-growth onto the hydroxyapatite coating associated with loading flexural micro-motion leads to hydroxyapatite being pulled off the smooth stem substrate in zone 1. Progressive delamination of the hydroxyapatite then occurs. The triple-tapered design though imparts continued stability. We report high loosening rates in the Corail stem and suggest a mechanism for its development.
The objectives of this study were: 1) to examine osteophyte formation, subchondral bone advance, and bone marrow lesions (BMLs) in osteoarthritis (OA)-prone Hartley guinea pigs; and 2) to assess the disease-modifying activity of an orally administered phosphocitrate ‘analogue’, Carolinas Molecule-01 (CM-01). Young Hartley guinea pigs were divided into two groups. The first group (n = 12) had drinking water and the second group (n = 9) had drinking water containing CM-01. Three guinea pigs in each group were euthanized at age six, 12, and 18 months, respectively. Three guinea pigs in the first group were euthanized aged three months as baseline control. Radiological, histological, and immunochemical examinations were performed to assess cartilage degeneration, osteophyte formation, subchondral bone advance, BMLs, and the levels of matrix metalloproteinse-13 (MMP13) protein expression in the knee joints of hind limbs.Objectives
Methods
The aims of this study were to evaluate the clinical and radiological
outcomes of the Universal-2 total wrist arthroplasty (TWA) in patients
with rheumatoid arthritis. This was a retrospective review of all 95 Universal-2 TWAs which
were performed in our institution between 2003 to 2012 in patients
with rheumatoid arthritis. A total of six patients were lost to
follow-up and two died of unrelated causes. A total of ten patients
had bilateral procedures. Accordingly, 75 patients (85 TWAs) were
included in the study. There were 59 women and 16 men with a mean
age of 59 years (26 to 86). The mean follow-up was 53 months (24
to 120). Clinical assessment involved recording pain on a visual
analogue score, range of movement, grip strength, the Quick Disabilities
of the Arm, Shoulder and Hand (DASH) and Wrightington wrist scores.
Any adverse effects were documented with particular emphasis on
residual pain, limitation of movement, infection, dislocation and
the need for revision surgery. Radiographic assessment was performed pre-operatively and at
three, six and 12 months post-operatively, and annually thereafter.
Arthroplasties were assessed for distal row intercarpal fusion and
loosening. Radiolucent zones around the components were documented
according to a system developed at our institution.Aims
Patients and Methods
Our aim was to perform a systematic review of the literature
to assess the incidence of post-operative epidural haematomas and
wound infections after one-, or two-level, non-complex, lumbar surgery
for degenerative disease in patients with, or without post-operative
wound drainage. Studies were identified from PubMed and EMBASE, up to and including
27 August 2015, for papers describing one- or two-level lumbar discectomy
and/or laminectomy for degenerative disease in adults which reported
any form of subcutaneous or subfascial drainage.Aims
Patients and Methods
Perthes disease is a childhood disorder often resulting in femoral head deformity. Categorical/dichotomous outcomes of deformity are typical clinically, however quantitative, continuous measures, such as Sphericity Deviation Score (SDS), are critical for studying interventions. SDS uses radiographs in two planes to quantify femoral head deformity. Limitations of SDS may include non-orthogonal planes and lost details due to projections. We applied this method in 3D, with specific objectives to: 1. Develop SDS-like sphericity measures from 3D data 2. Obtain 2D and 3D sphericity for normal and Perthes hips 3. Compare slice-based (3D) and projection-based (2D) sphericity CT images of 16 normal (8 subjects) and 5 Perthes hips (4 subjects) were segmented to create 3D hip models. Ethics board approval was obtained for this study. SDS consists of roundness error (RE) in two planes and ellipsoid deformation (ED) between planes. We implemented a modified SDS which was applied to (a) orthogonal projections simulating radiographs (sagittal/coronal; 2D-mSDS), and (b) largest radii slices (sagittal/coronal; 3D-mSDS). Mean 2D-mSDS was higher for Perthes (27.2 (SD 11.4)) than normal (11.9 (SD 4.1)). Mean 3D-mSDS showed similar trends, but was higher than 2D (Perthes 33.6 (SD 5.3), normals 17.0 (SD 3.1)). Unlike 2D-mSDS, 3D-mSDS showed no overlap between groups. For Perthes hips, 2D-mSDS was consistent with SDS. For normal hips, 2D-mSDS was higher than expected (similar to Stulberg II). Projection-based (2D) measures may produce lower mSDS due to spatial averaging. Slice-based (3D) measures may better distinguish between normal and Perthes shapes, which may better differentiate effectiveness of treatments.
The accurate assessment of skeletal maturity
is essential in the management of orthopaedic conditions in the growing
child. In order to identify the time of peak height velocity (PHV)
in adolescents, two systems for assessing skeletal maturity have
been described recently; the calcaneal apophyseal ossification method
and the Sanders hand scores. The purpose of this study was to compare these methods in assessing
skeletal maturity relative to PHV. We studied the radiographs of
a historical group of 94 healthy children (49 females and 45 males),
who had been followed longitudinally between the ages of three and
18 years with serial radiographs and physical examination. Radiographs
of the foot and hand were undertaken in these children at least
annually between the ages of ten and 15 years. We reviewed 738 radiographs
of the foot and 694 radiographs of the hand. PHV was calculated
from measurements of height taken at the time of the radiographs. Prior to PHV we observed four of six stages of calcaneal apophyseal
ossification and two of eight Sanders stages. Calcaneal stage 3
and Sanders stage 2 was seen to occur about 0.9 years before PHV,
while calcaneal stage 4 and Sanders stage 3 occurred approximately
0.5 years after PHV. The stages of the calcaneal and Sanders systems can be used in
combination, offering better assessment of skeletal maturity with
respect to PHV than either system alone. Cite this article:
The aim of our study was to describe the characteristics,
treatment, and outcomes of patients with periprosthetic joint infection
(PJI) and normal inflammatory markers after total knee arthroplasty
(TKA) and total hip arthroplasty (THA). In total 538 TKAs and 414 THAs underwent surgical treatment for
PJI and met the inclusion criteria. Pre-operative erythrocyte sedimentation
rate (ESR) and C-reactive protein level (CRP) were reviewed to identify
the seronegative cohort. An age- and gender-matched cohort was identified
from the remaining patients for comparison. Overall, 4% of confirmed
infections were seronegative (21 TKA and 17 THA). Of those who underwent
pre-operative aspiration, cultures were positive in 76% of TKAs
(n = 13) and 64% of THAs (n = 7). Cell count and differential were
suggestive of infection in 85% of TKA (n = 11) and all THA aspirates
(n = 5). The most common organism was coagulase-negative Cite this article:
A retrospective review was performed of patients
undergoing primary cementless total knee replacement (TKR) using
porous tantalum performed by a group of surgical trainees. Clinical
and radiological follow-up involved 79 females and 26 males encompassing
115 knees. The mean age was 66.9 years (36 to 85). Mean follow-up
was 7 years (2 to 11). Tibial and patellar components were porous
tantalum monoblock implants, and femoral components were posterior
stabilised (PS) in design with cobalt–chromium fibre mesh. Radiological
assessments were made for implant positioning, alignment, radiolucencies,
lysis, and loosening. There was 95.7% survival of implants. There
was no radiological evidence of loosening and no osteolysis found.
No revisions were performed for aseptic loosening. Average tibial
component alignment was 1.4° of varus (4°of valgus to 9° varus),
and 6.2° (3° anterior to 15° posterior) of posterior slope. Mean
femoral component alignment was 6.6° (1° to 11°) of valgus. Mean tibiofemoral
alignment was 5.6° of valgus (7° varus to 16° valgus). Patellar
tilt was a mean of 2.4° lateral (5° medial to 28° lateral). Patient
satisfaction with improvement in pain was 91%. Cementless TKR incorporating
porous tantalum yielded good clinical and radiological outcomes
at a mean of follow-up of seven-years. Cite this article:
Although it is clear that opening-wedge high
tibial osteotomy (HTO) changes alignment in the coronal plane, which is
its objective, it is not clear how this procedure affects knee kinematics
throughout the range of joint movement and in other planes. Our research question was: how does opening-wedge HTO change
three-dimensional tibiofemoral and patellofemoral kinematics in
loaded flexion in patients with varus deformity?Three-dimensional
kinematics were assessed over 0° to 60° of loaded flexion using
an MRI method before and after opening-wedge HTO in a cohort of
13 men (14 knees). Results obtained from an iterative statistical
model found that at six and 12 months after operation, opening-wedge
HTO caused increased anterior translation of the tibia (mean 2.6
mm, p <
0.001), decreased proximal translation of the patella
(mean –2.2 mm, p <
0.001), decreased patellar spin (mean –1.4°,
p <
0.05), increased patellar tilt (mean 2.2°, p <
0.05) and
changed three other parameters. The mean Western Ontario and McMaster
Universities Arthritis Index improved significantly (p <
0.001)
from 49.6 (standard deviation ( The three-dimensional kinematic changes found may be important
in explaining inconsistency in clinical outcomes, and suggest that
measures in addition to coronal plane alignment should be considered. Cite this article:
Malpositioning of the trochanteric entry point
during the introduction of an intramedullary nail may cause iatrogenic
fracture or malreduction. Although the optimal point of insertion
in the coronal plane has been well described, positioning in the
sagittal plane is poorly defined. The paired femora from 374 cadavers were placed both in the anatomical
position and in internal rotation to neutralise femoral anteversion.
A marker was placed at the apparent apex of the greater trochanter,
and the lateral and anterior offsets from the axis of the femoral
shaft were measured on anteroposterior and lateral photographs. Greater
trochanteric morphology and trochanteric overhang were graded. The mean anterior offset of the apex of the trochanter relative
to the axis of the femoral shaft was 5.1 mm ( Placement of the entry position at the apex of the greater trochanter
in the anteroposterior view does not reliably centre an intramedullary
nail in the sagittal plane. Based on our findings, the site of insertion
should be about 5 mm posterior to the apex of the trochanter to
allow for its anterior offset. Cite this article:
Treatment of an infected total elbow replacement
(TER) is often successful in eradicating or suppressing the infection.
However, the extensor mechanism may be compromised by both the infection
and the surgery. The goal of this study was to assess triceps function
in patients treated for deep infection complicating a TER. Between
1976 and 2007 a total of 217 TERs in 207 patients were treated for
infection of a TER at our institution. Superficial infections and
those that underwent resection arthroplasty were excluded, leaving
93 TERs. Triceps function was assessed by examination and a questionnaire.
Outcome was measured using the Mayo Elbow Performance Score (MEPS). Triceps weakness was identified in 51 TERs (49 patients, 55%).
At a mean follow-up of five years (0.8 to 34), the extensor mechanism
was intact in 13 patients, with the remaining 38 having bone or
soft-tissue loss. The mean MEPS was 70 points (5 to 100), with a
mean functional score of 18 (0 to 25) of a possible 25 points. Infection following TER can often be eradicated; however, triceps
weakness occurs in more than half of the patients and may represent
a major functional problem. Cite this article:
We aimed to determine the effect of surgical approach on the
histology of the femoral head following resurfacing of the hip. We performed a histological assessment of the bone under the
femoral component taken from retrieval specimens of patients having
revision surgery following resurfacing of the hip. We compared the
number of empty lacunae in specimens from patients who had originally
had a posterior surgical approach with the number in patients having alternative
surgical approaches.Objectives
Methods
