We studied the effect of vitamin C on fracture healing in the elderly. A total of 80 elderly Osteogenic Disorder Shionogi rats were divided into four groups with different rates of vitamin C intake. A closed bilateral fracture was made in the middle third of the femur of each rat. Five weeks after fracture the femora were analysed by mechanical and histological testing. The groups with the lower vitamin C intake demonstrated a lower mechanical resistance of the healing callus and a lower histological grade. The vitamin C levels in blood during healing correlated with the torque resistance of the callus formed (
Studies on the migration of an implant may be the only way of monitoring the early performance of metal-on-metal prostheses. The Ein Bild Roentgen Analyse - femoral component analysis (EBRA-FCA) method was adapted to measure migration of the femoral component in a metal-on-metal surface arthroplasty of the hip using standard antero-posterior radiographs. In order to determine the accuracy and precision of this method a prosthesis was implanted into cadaver bones. Eleven series of radiographs were used to perform a zero-migration study. After adjustment of the femoral component to simulate migration of 3 mm the radiographs were repeated. All were measured independently by three different observers. The accuracy of the method was found to be ± 1.6 mm for the x-direction and ± 2 mm for the y-direction (95% percentile). The method was validated using 28 hips with a minimum follow-up of 3.5 years after arthroplasty. Seventeen were sound, but 11 had failed because of loosening of the femoral component. The normal (control) group had a different pattern of migration compared with that of the loose group. At 29.2 months, the control group showed a mean migration of 1.62 mm and 1.05 mm compared with 4.39 mm and 4.05 mm in the failed group, for the centre of the head and the tip of the stem, respectively (p = 0.001). In the failed group, the mean time to migration greater than 2 mm was earlier than the onset of clinical symptoms or radiological evidence of failure, 19.1 EBRA-FCA is a reliable and valid tool for measuring migration of the femoral component after surface arthroplasty and can be used to predict early failure of the implant. It may be of value in determining the long-term performance of surface arthroplasty.
We reviewed the medical records of 115 patients with 130 hips with developmental dysplasia with complete dislocation in the absence of a neuromuscular disorder, spontaneous reduction with a Pavlik harness, and a minimum of 14 years’ follow-up. The mean age at the time of harness application was 4.8 months (1 to 12) and the mean time spent in the harness was 6.1 months (3 to 12). A total of 108 hips (83.1%) were treated with the harness alone and supplementary surgery for residual acetabular dysplasia, as defined by an acetabular index >
30°, was performed in 22 hips (16.9%). An overall satisfactory outcome (Severin grade I or II) was achieved in 119 hips (91.5%) at a mean follow-up of 16 years (14 to 32) with a follow-up rate of 75%. Avascular necrosis of the femoral head was noted in 16 hips (12.3%), seven of which (44%) underwent supplementary surgery and nine (56%) of which were classified as satisfactory. The acetabular index was the most reliable predictor of residual acetabular dysplasia.
We have studied 180 patients (128 men and 52 women) who had undergone lumbar discectomy at a mean of 25.4 years (20 to 32) after operation. Pre-operatively, most patients (70 patients; 38.9%) had abnormal reflexes and/or muscle weakness in the leg (96 patients; 53.3%). At follow-up 42 patients (60%) with abnormal reflexes pre-operatively had fully recovered and 72 (75%) with pre-operative muscle impairment had normal muscle strength. When we looked at patient-reported outcomes, we found that the Short form-36 summary scores were similar to the aged-matched normative values. No disability or minimum disability on the Oswestry disability index was reported by 136 patients (75.6%), and 162 (90%) were satisfied with their operation. The most important predictors of patients’ self-reported positive outcome were male gender and higher educational level. No association was detected between muscle recovery and outcome. Most patients who had undergone lumbar discectomy had long-lasting neurological recovery. If the motor deficit persists after operation, patients can still expect a long-term satisfactory outcome, provided that they have relief from pain immediately after surgery.
The benefit of arthroscopy of the hip in the
treatment of femoroacetabular impingement (FAI) in terms of quality
of life (QoL) has not been reported. We prospectively collected
data on 612 patients (257 women (42%) and 355 men (58%)) with a
mean age at the time of surgery of 36.7 years (14 to 75) who underwent
arthroscopy of the hip for FAI under the care of a single surgeon.
The minimum follow-up was one year (mean 3.2 years (1 to 7)). The
responses to the modified Harris hip score were translated using
the Rosser Index Matrix in order to provide a QoL score. The mean
QoL score increased from 0.946 (-1.486 to 0.995) to 0.974 (0.7 to
1) at one year after surgery (p <
0.001). The mean QoL score
in men was significantly higher than in women, both before and one
year after surgery (both p <
0.001). However, the mean change
in the QoL score was not statistically different between men and
women (0.02 (-0.21 to 0.27) and 0.04 (-0.16 to 0.87), respectively;
p = 0.12). Linear regression analysis revealed that the significant predictors
of a change in QoL score were pre-operative QoL score (p <
0.001)
and gender (p = 0.04). The lower the pre-operative score, the higher
the gain in QoL post-operatively (ρ = -0.66; p <
0.001). One
year after surgery the QoL scores in the 612 patients had improved
in 469 (76.6%), remained unchanged in 88 (14.4%) and had deteriorated
in 55 (9.0%).
A variety of radiological methods of measuring
version of the acetabular component after total hip replacement (THR)
have been described. The aim of this study was to evaluate the reliability
and validity of six methods (those of Lewinnek; Widmer; Hassan et
al; Ackland, Bourne and Uhthoff; Liaw et al; and Woo and Morrey)
that are currently in use. In 36 consecutive patients who underwent
THR, version of the acetabular component was measured by three independent
examiners on plain radiographs using these six methods and compared
with measurements using CT scans. The intra- and interobserver reliabilities
of each measurement were estimated. All measurements on both radiographs
and CT scans had excellent intra- and interobserver reliability
and the results from each of the six methods correlated well with
the CT measurements. However, measurements made using the methods
of Widmer and of Ackland, Bourne and Uhthoff were significantly
different from the CT measurements (both p <
0.001), whereas
measurements made using the remaining four methods were similar
to the CT measurements. With regard to reliability and convergent
validity, we recommend the use of the methods described by Lewinnek,
Hassan et al, Liaw et al and Woo and Morrey for measurement of version
of the acetabular component.
The aim of this retrospective cohort study was
to identify any difference in femoral offset as measured on pre-operative
anteroposterior (AP) radiographs of the pelvis, AP radiographs of
the hip and corresponding CT scans in a consecutive series of 100
patients with primary end-stage osteoarthritis of the hip (43 men
and 57 women with a mean age of 61 years (45 to 74) and a mean body
mass index of 28 kg/m2 (20 to 45)). Patients were positioned according to a standardised protocol
to achieve reproducible projection and all images were calibrated.
Inter- and intra-observer reliability was evaluated and agreement
between methods was assessed using Bland-Altman plots. In the entire cohort, the mean femoral offset was 39.0 mm (95%
confidence interval (CI) 37.4 to 40.6) on radiographs of the pelvis,
44.0 mm (95% CI 42.4 to 45.6) on radiographs of the hip and 44.7
mm (95% CI 43.5 to 45.9) on CT scans. AP radiographs of the pelvis
underestimated femoral offset by 13% when compared with CT (p <
0.001).
No difference in mean femoral offset was seen between AP radiographs
of the hip and CT (p = 0.191). Our results suggest that femoral offset is significantly underestimated
on AP radiographs of the pelvis but can be reliably and accurately
assessed on AP radiographs of the hip in patients with primary end-stage
hip osteoarthritis. We, therefore, recommend that additional AP radiographs of the
hip are obtained routinely for the pre-operative assessment of femoral
offset when templating before total hip replacement.
This prospective study evaluates the role of new laboratory markers in the diagnosis of deep implant infection in 78 patients (41 men and 37 women) with a revision total knee or hip replacement. The mean age at the time of operation was 64.0 years (19 to 90). Intra-operative cultures showed that 21 patients had a septic and 57 an aseptic total joint replacement. The white blood cell count, the erythrocyte sedimentation rate and levels of C-reactive protein, interleukin-6, procalcitonin and tumour necrosis factor (TNF)-α were measured in blood samples before operation. The diagnostic cut-off values were determined by Received Operating Characteristic curve analysis. C-reactive protein (>
3.2 md/dl) and interleukin-6 (>
12 pg/ml) have the highest sensitivity (0.95). Interleukin-6 is less specific than C-reactive protein (0.87 The combination of C-reactive protein and interleukin-6 measurement provide excellent screening tests for infection of a deep implant. A highly specific marker such as procalcitonin and pre-operative aspiration of the joint might be useful in identifying patients with true positive C-reactive protein and/or interleukin-6 levels.
We report a prospective analysis of clinical
outcome in patients treated with medial patellofemoral ligament
(MPFL) reconstruction using an autologous semitendinosus graft.
The technique includes superolateral portal arthroscopic assessment
before and after graft placement to ensure correct graft tension
and patellar tracking before fixation. Between October 2005 and
October 2010, a total of 201 consecutive patients underwent 219 procedures.
Follow-up is presented for 211 procedures in 193 patients with a
mean age of 26 years (16 to 49), and mean follow-up of 16 months
(6 to 42). Indications were atraumatic recurrent patellar dislocation
in 141 patients, traumatic recurrent dislocation in 50, pain with
subluxation in 14 and a single dislocation with persistent instability
in six. There have been no recurrent dislocations/subluxations.
There was a statistically significant improvement between available pre-
and post-operative outcome scores for 193 patients (all p <
0.001).
Female patients with a history of atraumatic recurrent dislocation
and all patients with history of previous surgery had a significantly
worse outcome (all p <
0.05). The indication for surgery, degree
of dysplasia, associated patella alta, time from primary dislocation
to surgery and evidence of associated cartilage damage at operation
did not result in any significant difference in outcome. This series adds considerably to existing evidence that MPFL
reconstruction is an effective surgical procedure for selected patients
with patellofemoral instability.
Modern metal-on-metal bearings produce less wear debris and osteolysis, but have the potential adverse effect of release of ions. Improved ceramic-on-ceramic bearings have the lowest wear of all, but the corrosion process has not been analysed. Our aim was to measure the serum ion release (ng/ml) in 23 patients having stable hip prostheses with a ceramic-on-ceramic coupling (group A) and to compare it with the release in 42 patients with a metal-on-metal bearing (group B) in the medium term. Reference values were obtained from a population of 47 healthy subjects (group C). The concentrations of chromium, cobalt, aluminium and titanium were measured. There was a significant increase of cobalt, chromium and aluminium levels (p <
0.05) in group B compared with groups A and C. Group A did not differ significantly from the control group. Despite the apparent advantage of a metal-on-metal coupling, especially in younger patients with a long life expectancy, a major concern arises regarding the extent and duration of ion exposure. For this reason, the low corrosion level in a ceramic-on-ceramic coupling could be advantageous.
Increasing numbers of posterior lumbar fusions
are being performed. The purpose of this study was to identify trends
in demographics, mortality and major complications in patients undergoing
primary posterior lumbar fusion. We accessed data collected for
the Nationwide Inpatient Sample for each year between 1998 and 2008
and analysed trends in the number of lumbar fusions, mean patient
age, comorbidity burden, length of hospital stay, discharge status,
major peri-operative complications and mortality. An estimated 1 288 496
primary posterior lumbar fusion operations were performed between
1998 and 2008 in the United States. The total number of procedures,
mean patient age and comorbidity burden increased over time. Hospital
length of stay decreased, although the in-hospital mortality (adjusted
and unadjusted for changes in length of hospital stay) remained
stable. However, a significant increase was observed in peri-operative
septic, pulmonary and cardiac complications. Although in-hospital mortality
rates did not change over time in the setting of increases in mean
patient age and comorbidity burden, some major peri-operative complications
increased. These trends highlight the need for appropriate peri-operative services
to optimise outcomes in an increasingly morbid and older population
of patients undergoing lumbar fusion.
We report an independent prospective review of the first 230 Birmingham hip resurfacings in 212 patients at a mean follow-up of five years (4 to 6). Two patients, one with a loose acetabular component and the other with suspected avascular necrosis of the femoral head, underwent revision. There were two deaths from unrelated causes and one patient was lost to follow-up. The survivorship with the worst-case scenario was 97.8% (95% confidence interval 95.8 to 99.5). The mean Harris hip score improved significantly (paired On radiological review at five years, one patient had a progressive lucent line around the acetabular component and six had progressive lucent lines around the femoral component. A total of 18 femoral components (8%) had migrated into varus and those with lucent lines present migrated a mean of 3.8° (1.02° to 6.54°) more than the rest. Superolateral notching of the femoral neck and reactive sclerosis at the tip of the peg of the femoral component were associated with the presence of lucent lines (chi-squared test, p <
0.05), but not with migration of the femoral component, and are of unknown significance. Our results with the Birmingham hip resurfacing continue to be satisfactory at a mean follow-up of five years.
This study evaluated the effect of limb lengthening
on longitudinal growth in patients with achondroplasia. Growth of
the lower extremity was assessed retrospectively by serial radiographs
in 35 skeletally immature patients with achondroplasia who underwent
bilateral limb lengthening (Group 1), and in 12 skeletally immature
patients with achondroplasia who did not (Group 2). In Group 1,
23 patients underwent only tibial lengthening (Group 1a) and 12 patients
underwent tibial and femoral lengthening sequentially (Group 1b). The mean lengthening in the tibia was 9.2 cm (59.5%) in Group
1a, and 9.0 cm (58.2%) in the tibia and 10.2 cm (54.3%) in the femur
in Group 1b. The mean follow-up was 9.3 years (8.6 to 10.3). The
final mean total length of lower extremity in Group 1a was 526.6
mm (501.3 to 552.9) at the time of skeletal maturity and 610.1 mm
(577.6 to 638.6) in Group 1b, compared with 457.0 mm (411.7 to 502.3)
in Group 2. However, the mean actual length, representing the length
solely grown from the physis without the length of distraction,
showed that there was a significant disturbance of growth after
limb lengthening. In Group 1a, a mean decrease of 22.4 mm (21.3
to 23.1) (4.9%) was observed in the actual limb length when compared
with Group 2, and a greater mean decrease of 38.9 mm (37.2 to 40.8)
(8.5%) was observed in Group 1b when compared with Group 2 at skeletal
maturity. In Group 1, the mean actual limb length was 16.5 mm (15.8 to
17.2) (3.6%) shorter in Group 1b when compared with Group 1a at
the time of skeletal maturity. Premature physeal closure was seen
mostly in the proximal tibia and the distal femur with relative
preservation of proximal femur and distal tibia. We suggest that significant disturbance of growth can occur after
extensive limb lengthening in patients with achondroplasia, and
therefore, this should be included in pre-operative counselling
of these patients and their parents.
Different calcaneal plates with locked screws were compared in an experimental model of a calcaneal fracture. Four plate models were tested, three with uniaxially-locked screws (Synthes, Newdeal, Darco), and one with polyaxially-locked screws (90° ± 15°) (Rimbus). Synthetic calcanei were osteotomised to create a fracture model and then fixed with the plates and screws. Seven specimens for each plate model were subjected to cyclic loading (preload 20 N, 1000 cycles at 800 N, 0.75 mm/s), and load to failure (0.75 mm/s). During cyclic loading, the plate with polyaxially-locked screws (Rimbus) showed significantly lower displacement in the primary loading direction than the plates with uniaxially-locked screws (mean values of maximum displacement during cyclic loading: Rimbus, 3.13 mm ( The increased stability of a plate with polyaxially-locked screws demonstrated during cyclic loading compared with plates with uniaxially-locked screws may be beneficial for clinical use.
In this meta-analysis we included 32 English-language articles published between January 1975 and June 2004 on the diagnostic performance of plain radiography, subtraction arthrography, nuclear arthrography and bone scintigraphy in detecting aseptic loosening of the femoral component, using criteria based on the Cochrane systematic review of screening and diagnostic tests. The mean sensitivity and specificity were, respectively, 82% (95% confidence interval (CI) 76 to 87) and 81% (95% CI 73 to 87) for plain radiography and 85% (95% CI 75 to 91) and 83% (95% CI 75 to 89) for nuclear arthrography. Pooled sensitivity and specificity were, respectively, 86% (95% CI 74 to 93) and 85% (95% CI 77 to 91) for subtraction arthrography and 85% (95% CI 79 to 89) and 72% (95% CI 64 to 79) for bone scintigraphy. Although the diagnostic performance of the imaging techniques was not significantly different, plain radiography and bone scintigraphy are preferred for the assessment of a femoral component because of their efficacy and lower risk of patient morbidity.
We performed a retrospective examination of the
anteroposterior pelvic CT scout views of 419 randomly selected patients between
April 2004 and August 2009 in order to determine the prevalence
of cam-type femoroacetabular deformity in the asymptomatic population.
The CT scans had all been undertaken for conditions unrelated to
disorders of the hip. The frequency of cam-type femoroacetabular
deformity was assessed by measuring the α-angle of each hip on the
anteroposterior images. The α-angles were classified according to
the Copenhagen Osteoarthritis Study. Among 215 male hips (108 patients)
the mean α-angle was 59.12° (37.75° to 103.50°). Of these, a total
of 30 hips (13.95%) were defined as pathological, 32 (14.88%) as
borderline and 153 (71.16%) as normal. Among 540 female hips (272
patients) the mean α-angle was 45.47° (34.75° to 87.00°), with 30
hips (5.56%) defined as pathological, 33 (6.11%) as borderline and
477 (88.33%) as normal. It appears that the cam-type femoroacetabular
deformity is not rare among the asymptomatic population. These anatomical
abnormalities, as determined by an increased α-angle, appear to
be twice as frequent in men as in women. Although an association
between osteoarthritis and femoroacetabular impingement is believed
to exist, a long-term epidemiological study is needed to determine
the natural history of these anatomical abnormalities.
Lengthening of the humerus is now an established
technique. We compared the complications of humeral lengthening
with those of femoral lengthening and investigated whether or not
the callus formation in the humerus proceeds at a higher rate than
that in the femur. A total of 24 humeral and 24 femoral lengthenings
were performed on 12 patients with achondroplasia. We measured the
pixel value ratio (PVR) of the lengthened area on radiographs and
each radiograph was analysed for the shape, type and density of
the callus. The quality of life (QOL) of the patients after humeral
lengthening was compared with that prior to surgery. The complication
rate per segment of humerus and femur was 0.87% and 1.37%, respectively.
In the humerus the PVR was significantly higher than that of the
femur. Lower limbs were associated with an increased incidence of
concave, lateral and central callus shapes. Humeral lengthening
had a lower complication rate than lower-limb lengthening, and QOL
increased significantly after humeral lengthening. Callus formation
in the humerus during the distraction period proceeded at a significantly
higher rate than that in the femur. These findings indicate that humeral lengthening has an important
role in the management of patients with achondroplasia.
We developed a questionnaire to assess patient-reported outcome after surgery of the elbow from interviews with patients. Initially, 17 possible items with five response options were included. A prospective study of 104 patients (107 elbow operations) was carried out to analyse the underlying factor structure, dimensionality, internal and test-retest reliability, construct validity and responsiveness of the questionnaire items. This was compared with the Mayo Elbow performance score clinical scale, the Disabilities of the Arm, Shoulder and Hand questionnaire, and the Short-Form (SF-36) General Health Survey. In total, five questions were considered inappropriate, which resulted in the final 12-item questionnaire, which has been referred to as the Oxford elbow score. This comprises three unidimensional domains, ‘elbow function’, ‘pain’ and ‘social-psychological’; with each domain comprising four items with good measurement properties. This new 12-item Oxford elbow score is a valid measure of the outcome of surgery of the elbow.
Using inaccurate quotations can propagate misleading
information, which might affect the management of patients. The
aim of this study was to determine the predictors of quotation inaccuracy
in the peer-reviewed orthopaedic literature related to the scaphoid.
We randomly selected 100 papers from ten orthopaedic journals. All references
were retrieved in full text when available or otherwise excluded.
Two observers independently rated all quotations from the selected
papers by comparing the claims made by the authors with the data
and expressed opinions of the reference source. A statistical analysis
determined which article-related factors were predictors of quotation
inaccuracy. The mean total inaccuracy rate of the 3840 verified
quotes was 7.6%. There was no correlation between the rate of inaccuracy
and the impact factor of the journal. Multivariable analysis identified
the journal and the type of study (clinical, biomechanical, methodological,
case report or review) as important predictors of the total quotation
inaccuracy rate. We concluded that inaccurate quotations in the peer-reviewed
orthopaedic literature related to the scaphoid were common and slightly
more so for certain journals and certain study types. Authors, reviewers
and editorial staff play an important role in reducing this inaccuracy.
We compared revision and mortality rates of 4668
patients undergoing primary total hip and knee replacement between
1989 and 2007 at a University Hospital in New Zealand. The mean
age at the time of surgery was 69 years (16 to 100). A total of
1175 patients (25%) had died at follow-up at a mean of ten years
post-operatively. The mean age of those who died within ten years
of surgery was 74.4 years (29 to 97) at time of surgery. No change
in comorbidity score or age of the patients receiving joint replacement
was noted during the study period. No association of revision or
death could be proven with higher comorbidity scoring, grade of
surgeon, or patient gender. We found that patients younger than 50 years at the time of surgery
have a greater chance of requiring a revision than of dying, those
around 58 years of age have a 50:50 chance of needing a revision,
and in those older than 62 years the prosthesis will normally outlast
the patient. Patients over 77 years old have a greater than 90%
chance of dying than requiring a revision whereas those around 47
years are on average twice as likely to require a revision than
die. This information can be used to rationalise the need for long-term
surveillance and during the informed consent process.