The April 2014 Hip & Pelvis Roundup360 looks at: Recent arthroplasty and flight; whether that squeak could be a fracture; diagnosing early infected hip replacement; impaction grafting at a decade; whether squeaking is more common than previously thought; femoral offset associated with post THR outcomes; and periprosthetic fracture stabilisation.
In a retrospective study we compared 32 HINTEGRA
total ankle replacements (TARs) and 35 Mobility TARs performed between
July 2005 and May 2010, with a minimum follow-up of two years. The
mean follow-up for the HINTEGRA group was 53 months (24 to 76) and
for the Mobility group was 34 months (24 to 45). All procedures
were performed by a single surgeon. There was no significant difference between the two groups with
regard to the mean AOFAS score, visual analogue score for pain or
range of movement of the ankle at the latest follow-up. Most radiological
measurements did not differ significantly between the two groups.
However, the most common grade of heterotopic ossification (HO)
was grade 3 in the HINTEGRA group (10 of 13 TARs, 76.9%) and grade
2 in the Mobility group (four of seven TARs, 57.1%) (p = 0.025).
Although HO was more frequent in the HINTEGRA group (40.6%) than
in the Mobility group (20.0%), this was not statistically significant
(p = 0.065).The difference in peri-operative complications between
the two groups was not significant, but intra-operative medial malleolar
fractures occurred in four (11.4%) in the Mobility group; four (12.5%)
in the HINTEGRA group and one TAR (2.9%) in the Mobility group failed
(p = 0.185). Cite this article:
Several radiological methods of measuring anteversion
of the acetabular component after total hip replacement (THR) have
been described. These studies used different definitions and reference
planes to compare methods, allowing for misinterpretation of the
results. We compared the reliability and accuracy of five current
methods using plain radiographs (those of Lewinnek, Widmer, Liaw,
Pradhan, and Woo and Morrey) with CT measurements, using the same
definition and reference plane. We retrospectively studied the plain
radiographs and CT scans in 84 hips of 84 patients who underwent
primary THR. Intra- and inter-observer reliability were high for
the measurement of inclination and anteversion with all methods
on plain radiographs and CT scans. The measurements of inclination on
plain radiographs were similar to the measurements using CT (p =
0.043). The mean difference between CT measurements was 0.6° (-5.9°
to 6.8°). Measurements using Widmer’s method were the most similar to those
using CT (p = 0.088), with a mean difference between CT measurements
of -0.9° (-10.4° to 9.1°), whereas the other four methods differed
significantly from those using CT (p <
0.001). This study has shown that Widmer’s method is the best for evaluating
the anteversion of the acetabular component on plain radiographs. Cite this article:
Although it has been suggested that the outcome
after revision of a unicondylar knee replacement (UKR) to total knee
replacement (TKR) is better when the mechanism of failure is understood,
a comparative study on this subject has not been undertaken. A total of 30 patients (30 knees) who underwent revision of their
unsatisfactory UKR to TKR were included in the study: 15 patients
with unexplained pain comprised group A and 15 patients with a defined
cause for pain formed group B. The Oxford knee score (OKS), visual
analogue scale for pain (VAS) and patient satisfaction were assessed before
revision and at one year after revision, and compared between the
groups. The mean OKS improved from 19 (10 to 30) to 25 (11 to 41) in
group A and from 23 (11 to 45) to 38 (20 to 48) in group B. The
mean VAS improved from 7.7 (5 to 10) to 5.4 (1 to 8) in group A
and from 7.4 (2 to 9) to 1.7 (0 to 8) in group B. There was a statistically
significant difference between the mean improvements in each group
for both OKS (p = 0.022) and VAS (p = 0.002). Subgroup analysis
in group A, performed in order to define a patient factor that predicts
outcome of revision surgery in patients with unexplained pain, showed
no pre-operative differences between both subgroups. These results may be used to inform patients about what to expect
from revision surgery, highlighting that revision of UKR to TKR
for unexplained pain generally results in a less favourable outcome
than revision for a known cause of pain. Cite this article:
We studied the bone mineral density (BMD) and
the bone mineral content (BMC) of the proximal tibia in patients with
a well-functioning uncemented Oxford medial compartment arthroplasty
using the Lunar iDXA bone densitometer. Our hypothesis was that
there would be decreased BMD and BMC adjacent to the tibial base
plate and increased BMD and BMC at the tip of the keel. There were 79 consecutive patients (33 men, 46 women) with a
mean age of 65 years (44 to 84) with a minimum two-year follow-up
(mean 2.6 years (2.0 to 5.0)) after unilateral arthroplasty, who
were scanned using a validated standard protocol where seven regions
of interest (ROI) were examined and compared with the contralateral
normal knee. All had well-functioning knees with a mean Oxford knee
score of 43 (14 to 48) and mean Knee Society function score of 90
(20 to 100), showing a correlation with the increasing scores and
higher BMC and BMD values in ROI 2 in the non-implanted knee relative
to the implanted knee (p = 0.013 and p = 0.015, respectively). The absolute and percentage changes in BMD and BMC were decreased
in all ROIs in the implanted knee compared with the non-implanted
knee, but this did not reach statistical significance. Bone loss
was markedly less than reported losses with total knee replacement. There was no significant association with side, although there
was a tendency for the BMC to decrease with age in men. The BMC
was less in the implanted side relative to the non-implanted side
in men compared with women in ROI 2 (p = 0.027), ROI 3 (p = 0.049)
and ROI 4 (p = 0.029). The uncemented Oxford medial compartment arthroplasty appears
to allow relative preservation of the BMC and BMD of the proximal
tibia, suggesting that the implant acts more physiologically than
total knee replacement. Peri-prosthetic bone loss is an important
factor in assessing long-term implant stability and survival, and
the results of this study are encouraging for the long-term outcome
of this arthroplasty. Cite this article:
Short uncemented humeral stems can preserve humeral
bone stock and facilitate revision surgery but may be prone to malalignment
or loosening, especially when used in reverse total shoulder replacement
(TSR). We undertook a retrospective review of 44 patients with a
mean age of 76 years (59 to 92) who underwent primary reverse TSR
with a short uncemented humeral stem. There were 29 females. The
indications for joint replacement included cuff tear associated
arthropathy (33), avascular necrosis (six), post-traumatic arthritis
(two), and inflammatory arthritis (three). At a mean follow-up of
27 months (24 to 40), pain was rated as mild or none in 43 shoulders
(97.7%). The mean active elevation improved from 54° Cite this article:
Bone sarcomas are rare cancers and orthopaedic
surgeons come across them infrequently, sometimes unexpectedly during
surgical procedures. We investigated the outcomes of patients who
underwent a surgical procedure where sarcomas were found unexpectedly
and were subsequently referred to our unit for treatment. We identified
95 patients (44 intra-lesional excisions, 35 fracture fixations,
16 joint replacements) with mean age of 48 years (11 to 83); 60%
were males (n = 57). Local recurrence arose in 40% who underwent
limb salvage surgery Cite this article:
The August 2013 Wrist &
Hand Roundup360 looks at: random group therapy is no good at treating OA of the hand; salvaging failed CMCJ arthroplasty; scaphocapitate arthrodesis for instability in manual workers; Brunelli tenodesis and scapholunate instability; night splints for Dupytren’s revisited; the smallest IM nail?; early diagnosis of CRPS?; and endoscopic carpal tunnel release?
We hypothesised that a large acromial cover with
an upwardly tilted glenoid fossa would be associated with degenerative
rotator cuff tears (RCTs), and conversely, that a short acromion
with an inferiorly inclined glenoid would be associated with glenohumeral
osteoarthritis (OA). This hypothesis was tested using a new radiological parameter,
the critical shoulder angle (CSA), which combines the measurements
of inclination of the glenoid and the lateral extension of the acromion
(the acromion index). The CSA was measured on standardised radiographs of three groups:
1) a control group of 94 asymptomatic shoulders with normal rotator
cuffs and no OA; 2) a group of 102 shoulders with MRI-documented
full-thickness RCTs without OA; and 3) a group of 102 shoulders
with primary OA and no RCTs noted during total shoulder replacement.
The mean CSA was 33.1° (26.8° to 38.6°) in the control group, 38.0°
(29.5° to 43.5°) in the RCT group and 28.1° (18.6° to 35.8°) in
the OA group. Of patients with a CSA >
35°, 84% were in the RCT
group and of those with a CSA <
30°, 93% were in the OA group. We therefore concluded that primary glenohumeral OA is associated
with significantly smaller degenerative RCTs with significantly
larger CSAs than asymptomatic shoulders without these pathologies.
These findings suggest that individual quantitative anatomy may
imply biomechanics that are likely to induce specific types of degenerative
joint disorders. Cite this article:
The three-dimensional (3D) correction of glenoid
erosion is critical to the long-term success of total shoulder replacement
(TSR). In order to characterise the 3D morphology of eroded glenoid
surfaces, we looked for a set of morphological parameters useful
for TSR planning. We defined a scapular coordinates system based
on non-eroded bony landmarks. The maximum glenoid version was measured
and specified in 3D by its orientation angle. Medialisation was
considered relative to the spino-glenoid notch. We analysed regular
CT scans of 19 normal (N) and 86 osteoarthritic (OA) scapulae. When
the maximum version of OA shoulders was higher than 10°, the orientation
was not only posterior, but extended in postero-superior (35%),
postero-inferior (6%) and anterior sectors (4%). The medialisation
of the glenoid was higher in OA than normal shoulders. The orientation
angle of maximum version appeared as a critical parameter to specify
the glenoid shape in 3D. It will be very useful in planning the
best position for the glenoid in TSR. Cite this article:
Mobile-bearing (MB) total knee replacement (TKR)
was introduced to reduce the risk of aseptic loosening and wear of
polyethylene inserts. However, no consistent clinical advantages
of mobile- over fixed-bearing (FB) TKR have been found. In this
study we evaluated whether mobile bearings have an advantage over
fixed bearings with regard to revision rates and clinical outcome
scores. Furthermore, we determined which modifying variables affected
the outcome. A systematic search of the literature was conducted to collect
clinical trials comparing MB and FB in primary TKR. The primary
outcomes were revision rates for any reason, aseptic loosening and
wear. Secondary outcomes included range of movement, Knee Society
score (KSS), Oxford knee score (OKS), Short-Form 12 (SF-12) score
and radiological parameters. Meta-regression techniques were used
to explore factors modifying the observed effect. Our search yielded 1827 publications, of which 41 studies met
our inclusion criteria, comprising over 6000 TKRs. Meta-analyses
showed no clinically relevant differences in terms of revision rates,
clinical outcome scores or patient-reported outcome measures between
MB and FB TKRs. It appears that theoretical assumptions of superiority
of MB over FB TKR are not borne out in clinical practice. Cite this article:
Cartilage repair in terms of replacement, or
regeneration of damaged or diseased articular cartilage with functional tissue,
is the ‘holy grail’ of joint surgery. A wide spectrum of strategies
for cartilage repair currently exists and several of these techniques
have been reported to be associated with successful clinical outcomes
for appropriately selected indications. However, based on respective
advantages, disadvantages, and limitations, no single strategy, or
even combination of strategies, provides surgeons with viable options
for attaining successful long-term outcomes in the majority of patients.
As such, development of novel techniques and optimisation of current techniques
need to be, and are, the focus of a great deal of research from
the basic science level to clinical trials. Translational research
that bridges scientific discoveries to clinical application involves
the use of animal models in order to assess safety and efficacy
for regulatory approval for human use. This review article provides
an overview of animal models for cartilage repair. Cite this article:
The April 2014 Trauma Roundup360 looks at: is it safe to primarily close dog bite wounds?; conservative transfusion evidence based in hip fracture surgery; tibial nonunion is devastating to quality of life; sexual dysfunction after traumatic pelvic fracture; hemiarthroplasty versus fixation in displaced femoral neck fractures; silver VAC dressings “Gold Standard” in massive wounds; dual plating for talar neck fracture; syndesmosis and fibular length easiest errors in ankle fracture surgery; and dual mobility: stable as a rock in fracture.
The significance of weight in the indications
for unicompartmental knee replacement (UKR) is unclear. Our hypothesis was
that weight does not affect the long-term rate of survival of UKRs. We undertook a retrospective study of 212 UKRs at a mean follow-up
of 12 years (7 to 22). The patients were distributed according to
body mass index (BMI; <
The ten-year rates of survival were similar in the two weight
subgroups (≥ 82 kg: 93.5% (95% confidence interval (CI) 66.5 to
96.3); <
82 kg: 92.5% (95% CI 82.5 to 94.1)) and also in the
two BMI subgroups (≥ 30 kg/m2: 92% (95% CI 82.5 to 95.3);
<
30 kg/m2: 94% (95% CI 78.4 to 95.9)). Multimodal
regression analysis revealed that weight plays a part in reducing
the risk of revision with a relative risk of 0.387, although this
did not reach statistical significance (p = 0.662). The results
relating weight and BMI to the clinical outcome were not statistically
significant. Thus, this study confirms that weight does not influence
the long-term rate of survival of UKR. Cite this article:
To confirm whether developmental dysplasia of
the hip has a risk of hip impingement, we analysed maximum ranges
of movement to the point of bony impingement, and impingement location
using three-dimensional (3D) surface models of the pelvis and femur
in combination with 3D morphology of the hip joint using computer-assisted methods.
Results of computed tomography were examined for 52 hip joints with
DDH and 73 normal healthy hip joints. DDH shows larger maximum extension
(p = 0.001) and internal rotation at 90° flexion (p <
0.001).
Similar maximum flexion (p = 0.835) and external rotation (p = 0.713)
were observed between groups, while high rates of extra-articular
impingement were noticed in these directions in DDH (p <
0.001).
Smaller cranial acetabular anteversion (p = 0.048), centre-edge
angles (p <
0.001), a circumferentially shallower acetabulum,
larger femoral neck anteversion (p <
0.001), and larger alpha
angle were identified in DDH. Risk of anterior impingement in retroverted
DDH hips is similar to that in retroverted normal hips in excessive
adduction but minimal in less adduction. These findings might be
borne in mind when considering the possibility of extra-articular
posterior impingement in DDH being a source of pain, particularly
for patients with a highly anteverted femoral neck. Cite this article:
This study evaluated whether obese patients who
lost weight before their total joint replacement and kept it off post-operatively
were at lower risk of surgical site infection (SSI) and re-admission
compared with those who remained the same weight. We reviewed 444 patients who underwent a total hip replacement
and 937 with a total knee replacement who lost weight pre-operatively
and sustained their weight loss after surgery. After adjustments,
patients who lost weight before a total hip replacement and kept
it off post-operatively had a 3.77 (95% confidence interval (CI)
1.59 to 8.95) greater likelihood of deep SSIs and those who lost
weight before a total knee replacement had a 1.63 (95% CI 1.16 to
2.28) greater likelihood of re-admission compared with the reference
group. These findings raise questions about the safety of weight management
before total replacement of the hip and knee joints. Cite this article:
High-quality randomised controlled trials (RCTs)
evaluating surgical therapies are fundamental to the delivery of
evidence-based orthopaedics. Orthopaedic clinical trials have unique
challenges; however, when these challenges are overcome, evidence
from trials can be definitive in its impact on surgical practice.
In this review, we highlight several issues that pose potential
challenges to orthopaedic investigators aiming to perform surgical randomised
controlled trials. We begin with a discussion on trial design issues,
including the ethics of sham surgery, the importance of sample size,
the need for patient-important outcomes, and overcoming expertise
bias. We then explore features surrounding the execution of surgical
randomised trials, including ethics review boards, the importance
of organisational frameworks, and obtaining adequate funding. Cite this article: