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:
We performed a systematic review of the literature
to evaluate the use and interpretation of generic and disease-specific
functional outcome instruments in the reporting of outcome after
the surgical treatment of disruptions of the pelvic ring. A total
of 28 papers met our inclusion criteria, with eight reporting only
generic outcome instruments, 13 reporting only pelvis-specific outcome
instruments, and six reporting both. The Short-Form 36 (SF-36) was
by far the most commonly used generic outcome instrument, used in
12 papers, with widely variable reporting of scores. The pelvis-specific
outcome instruments were used in 19 studies; the Majeed score in
ten, Iowa pelvic score in six, Hannover pelvic score in two and
the Orlando pelvic score in one. Four sets of authors, all testing construct
validity based on correlation with the SF-36, performed psychometric
testing of three pelvis-specific instruments (Majeed, IPS and Orlando
scores). No testing of responsiveness, content validity, criterion
validity, internal consistency or reproducibility was performed. The existing literature in this area is inadequate to inform
surgeons or patients in a meaningful way about the functional outcomes
of these fractures after fixation.
There is great variability in acetabular component
orientation following hip replacement. The aims of this study were
to compare the component orientation at impaction with the orientation
measured on post-operative radiographs and identify factors that
influence the difference between the two. A total of 67 hip replacements
(52 total hip replacements and 15 hip resurfacings) were prospectively
studied. Intra-operatively, the orientation of the acetabular component
after impaction relative to the operating table was measured using
a validated stereo-photogrammetry protocol. Post-operatively, the
radiographic orientation was measured; the mean inclination/anteversion
was 43° ( This study demonstrated that in order to achieve a specific radiographic
orientation target, surgeons should implant the acetabular component
5° less inclined and 8° more anteverted than their target. Great
variability (2 Cite this article:
Orientation of the native acetabular plane as defined by the transverse acetabular ligament (TAL) and the posterior labrum was measured intra-operatively using computer-assisted navigation in 39 hips. In order to assess the influence of alignment on impingement, the range of movement was calculated for that defined by the TAL and the posterior labrum and compared with a standard acetabular component position (abduction 45°/anteversion 15°). With respect to the registration of the plane defined by the TAL and the posterior labrum, there was moderate interobserver agreement (r = 0.64, p <
0.001) and intra-observer reproducibility (r = 0.73, p <
0.001). The mean acetabular component orientation achieved was abduction of 41° (32° to 51°) and anteversion of 18° (−1° to 36°). With respect to the Lewinnek safe zone (abduction 40° ±10°, anteversion 15° ±10°), 35 of the 39 acetabular components were within this zone. However, there was no improvement in the range of movement (p = 0.94) and no significant difference in impingement (p = 0.085). Alignment of the acetabular component with the TAL and the posterior labrum might reduce the variability of acetabular component placement in total hip replacement. However, there is only a moderate interobserver agreement and intra-observer reliability in the alignment of the acetabular component using the TAL and the posterior labrum. No reduction in impingement was found when the acetabular component was aligned with the TAL and the posterior labrum, compared with a standard acetabular component position.
We have analysed a number of radiological measurements in an attempt to clarify the predisposing factors for degenerative spondylolisthesis of the lumbosacral junction. We identified 57 patients with a slip and a control group of 293 patients without any radiological abnormality apart from age-related changes. The relative thickness of the L5 transverse process, the sacral table angle and the height of the iliac crest were measured and evaluated. The difference in these measurements between men and women was analysed in the control group. We found that the transverse process of L5 was extremely slender, the sacral table more inclined, and the L5 vertebra was less deeply placed in the pelvis in patients with a slip compared with the control group. The differences in these three parameters were statistically significant. We believe that the L5 vertebra is predisposed to slip when these factors act together on a rigidly-stabilised sacrum. This occurs more commonly in women, probably as a result of constitutional differences in the development of the male and female spine.
Impingement syndrome in the shoulder has generally been considered to be a clinical condition of mechanical origin. However, anomalies exist between the pathology in the subacromial space and the degree of pain experienced. These may be explained by variations in the processing of nociceptive inputs between different patients. We investigated the evidence for augmented pain transmission (central sensitisation) in patients with impingement, and the relationship between pre-operative central sensitisation and the outcomes following arthroscopic subacromial decompression. We recruited 17 patients with unilateral impingement of the shoulder and 17 age- and gender-matched controls, all of whom underwent quantitative sensory testing to detect thresholds for mechanical stimuli, distinctions between sharp and blunt punctate stimuli, and heat pain. Additionally Oxford shoulder scores to assess pain and function, and PainDETECT questionnaires to identify ‘neuropathic’ and referred symptoms were completed. Patients completed these questionnaires pre-operatively and three months post-operatively. A significant proportion of patients awaiting subacromial decompression had referred pain radiating down the arm and had significant hyperalgesia to punctate stimulus of the skin compared with controls (unpaired The presence of either hyperalgesia or referred pain pre-operatively resulted in a significantly worse outcome from decompression three months after surgery (unpaired These observations confirm the presence of central sensitisation in a proportion of patients with shoulder pain associated with impingement. Also, if patients had relatively high levels of central sensitisation pre-operatively, as indicated by higher levels of punctate hyperalgesia and/or referred pain, the outcome three months after subacromial decompression was significantly worse.
We examined the relationships between the serum levels of chromium and cobalt ions and the inclination angle of the acetabular component and the level of activity in 214 patients implanted with a metal-on-metal resurfacing hip replacement. Each patient had a single resurfacing and no other metal in their body. All serum measurements were performed at a minimum of one year after operation. The inclination of the acetabular component was considered to be steep if the abduction angle was greater than 55°. There were significantly higher levels of metal ions in patients with steeply-inclined components (p = 0.002 for chromium, p = 0.003 for cobalt), but no correlation was found between the level of activity and the concentration of metal ions. A highly significant (p <
0.001) correlation with the arc of cover was found. Arcs of cover of less than 10 mm were correlated with a greater risk of high concentrations of serum metal ions. The arc of coverage was also related to the design of the component and to size as well as to the abduction angle of the acetabular component. Steeply-inclined acetabular components, with abduction angles greater than 55°, combined with a small size of component are likely to give rise to higher serum levels of cobalt and chromium ions. This is probably due to a greater risk of edge-loading.
We report the outcome of 32 patients (37 knees) who underwent hemicallostasis with a dynamic external fixator for osteoarthritis of the medial compartment of the knee. There were 16 men (19 knees) and 16 women (18 knees) with a mean age at operation of 54.6 years (27 to 72). The aim was to achieve a valgus overcorrection of 2° to 8° or mechanical axis at 62.5% (± 12.5%). At a mean follow-up of 62.8 months (51 to 81) there was no change in the mean range of movement, and no statistically significant difference in the Insall-Salvati index or tibial slope (p = 0.11 and p = 0.15, respectively). The mean hip-knee-ankle angle changed from 190.6 (183° to 197°) to 176.0° (171° to 181°), with a mean final position of the mechanical axis of 58.5% (35.1% to 71.2%). The desired alignment was attained in 31 of 37 (84%) knees. There were 21 excellent, 13 good, two fair and one poor result according to the Oxford knee score with no correlation between age and final score. This score was at its best at one year with a statistically significant deterioration at two years (p = 0.001) followed by a small but not statistically significant deterioration until the final follow-up (p = 0.17). All the knees with Ahlback grade 1 osteoarthritis had excellent or good results. Complications included pin tract infections involving 16.4% of all pins used, delayed union in two, knee stiffness in four, fracture of the lateral cortex in one and ring sequestrum in one. In conclusion, hemicallostasis provides precision in attaining the desired alignment without interfering with tibial slope or patellar height, and is relatively free of serious complications.
We evaluated the quality of guidelines on thromboprophylaxis
in orthopaedic surgery by examining how they adhere to validated
methodological standards in their development. A structured review
was performed for guidelines that were published between January
2005 and April 2013 in medical journals or on the Internet. A pre-defined
computerised search was used in MEDLINE, Scopus and Google to identify
the guidelines. The AGREE II assessment tool was used to evaluate
the quality of the guidelines in the study. Seven international and national guidelines were identified.
The overall methodological quality of the individual guidelines
was good. ‘Scope and Purpose’ (median score 98% interquartile range
(IQR)) 86% to 98%) and ‘Clarity of Presentation’ (median score 90%,
IQR 90% to 95%) were the two domains that received the highest scores. ‘Applicability’
(median score 68%, IQR 45% to 75%) and ‘Editorial Independence’
(median score 71%, IQR 68% to 75%) had the lowest scores. These findings reveal that although the overall methodological
quality of guidelines on thromboprophylaxis in orthopaedic surgery
is good, domains within their development, such as ‘Applicability’
and ‘Editorial Independence’, need to be improved. Application of
the AGREE II instrument by the authors of guidelines may improve
the quality of future guidelines and provide increased focus on
aspects of methodology used in their development that are not robust. Cite this article: Bone Joint J 2014;96-B:19–23.
Satisfaction is increasingly employed as an outcome
measure for a successful total knee replacement (TKR). Satisfaction
as an outcome measure encompasses many different intrinsic and extrinsic
factors related to a person’s experience before and after TKR. The
Swedish Knee Arthroplasty Registry has previously demonstrated on
a large population study that 17% of TKR recipients are not satisfied
with their TKR outcome. This finding has been replicated in other
countries. Similar significant factors emerged from these registry
studies that are related to satisfaction. It would appear that satisfaction
is better after more chronic diseases and whether the TKR results
in pain relief or improved function. Importantly, unmet pre-operative
expectations are a significant predictor for dissatisfaction following
a TKR. It may be possible to improve rates by addressing the issues
surrounding pain, function and expectation before embarking on surgery. Cite this article:
We report on gender-specific reference intervals
of the alpha angle and its association with other qualitative cam-type
findings in femoroacetabular impingement at the hip, according to
a population-based cohort of 2038 19-year-olds, 1186 of which were
women (58%). The alpha angle was measured on standardised frog-leg
lateral and anteroposterior (AP) views using digital measurement
software, and qualitative cam-type findings were assessed subjectively
on both views by independent observers. In all, 2005 participants
(837 men, 1168 women, mean age 18.6 years (17.2 to 20.1) were included
in the analysis. For the frog-leg view, the mean alpha angle (right
hip) was 47° (26 to 79) in men and 42° (29 to 76) in women, with
97.5 percentiles of 68° and 56°, respectively. For the AP view,
the mean values were 62° (40 to 105) and 52° (36 to 103) for men
and women, respectively, with 97.5 percentiles of 93° and 94°. Associations
between higher alpha angles and all qualitative cam-type findings
were seen for both genders on both views. The reference intervals
presented for the alpha angle in this cross-sectional study are
wide, especially for the AP view, with higher mean values for men
than women on both views. Cite this article:
We report the mid- to long-term (mean 20.3 years, 10 to 32.5) results of the Chiari pelvic osteotomy in patients with pre- to advanced stage osteoarthritis in dysplastic hips. We followed 163 Japanese patients (173 hips) with a mean age at surgery of 20 years (9 to 54). Overall, 124 hips (72%) had satisfactory results, with Harris hip scores ≥ 80. Satisfactory results were seen in 105 of 134 hips with pre- or early osteoarthritis (78%) and 19 of 39 hips with advanced osteoarthritis (49%). A total of 15 hips (9%) underwent a total hip replacement (THR) with a mean interval between osteotomy and THR of 16.4 years. With conversion to THR as the endpoint, the 30-year survival rate was 85.9% (95% confidence interval 82.3 to 89.5). It was 91.8% for patients with pre- or early osteoarthritis and 43.6% for those with advanced osteoarthritis (p < 0.001). We now perform the Chiari osteotomy for patients with dysplastic hips showing poor joint congruency and who prefer a joint-conserving procedure to THR.
Although the association between femoroacetabular impingement and osteoarthritis is established, it is not yet clear which hips have the greatest likelihood to progress rapidly to end-stage disease. We investigated the effect of several radiological parameters, each indicative of a structural aspect of the hip joint, on the progression of osteoarthritis. Pairs of plain anteroposterior pelvic radiographs, taken at least ten years apart, of 43 patients (43 hips) with a pistol-grip deformity of the femur and mild (Tönnis grade 1) or moderate (Tönnis grade 2) osteoarthritis were reviewed. Of the 43 hips, 28 showed evidence of progression of osteoarthritis. There was no significant difference in the prevalence of progression between hips with initial Tönnis grade 1 or grade 2 osteoarthritis (p = 0.31). Comparison of the hips with and without progression of arthritis revealed a significant difference in the mean medial proximal femoral angle (81° vs 87°, p = 0.004) and the presence of the posterior wall sign (39% vs 7%, p = 0.02) only. A logistic regression model was constructed to predict the influence of these two variables in the development of osteoarthritis. Mild to moderate osteoarthritis in hips with a pistol-grip deformity will not progress rapidly in all patients. In one-third, progression will take more than ten years to manifest, if ever. The individual geometry of the proximal femur and acetabulum partly influences this phenomenon. A hip with cam impingement is not always destined for end-stage arthritic degeneration.
We measured the tension in the interosseous membrane
in six cadaveric forearms using an Cite this article:
The Pirani scoring system, together with the Ponseti method of club foot management, was assessed for its predictive value. The data on 70 idiopathic club feet successfully treated by the Ponseti method and scored by Pirani’s system between February 2002 and May 2004 were analysed. There was a significant positive correlation between the initial Pirani score and number of casts required to correct the deformity. A foot scoring 4 or more is likely to require at least four casts, and one scoring less than 4 will require three or fewer. A foot with a hindfoot score of 2.5 or 3 has a 72% chance of requiring a tenotomy. The Pirani scoring system is reliable, quick, and easy to use, and provides a good forecast about the likely treatment for an individual foot but a low score does not exclude the possibility that a tenotomy may be required.
The medial approach for the treatment of children
with developmental dysplasia of the hip (DDH) in whom closed reduction
has failed requires minimal access with negligible blood loss. In
the United Kingdom, there is a preference for these children to
be treated using an anterolateral approach after the appearance
of the ossific nucleus. In this study we compared these two protocols,
primarily for the risk of osteonecrosis. Data were gathered prospectively for protocols involving the
medial approach (26 hips in 22 children) and the anterolateral approach
(22 hips in 21 children) in children aged <
24 months at the
time of surgery. Osteonecrosis of the femoral head was assessed
with validated scores. The acetabular index (AI) and centre–edge
angle (CEA) were also measured. The mean age of the children at the time of surgery was 11 months
(3 to 24) for the medial approach group and 18 months (12 to 24)
for the anterolateral group, and the combined mean follow-up was
70 months (26 to 228). Osteonecrosis of the femoral head was evident
or asphericity predicted in three of 26 hips (12%) in the medial approach
group and four of 22 (18%) in the anterolateral group (p = 0.52).
The mean improvement in AI was 8.8° (4° to 12°) and 7.9° (6° to
10°), respectively, at two years post-operatively (p = 0.18). There
was no significant difference in CEA values of affected hips between
the two groups. Children treated using an early medial approach did not have
a higher risk of developing osteonecrosis at early to mid-term follow-up
than those treated using a delayed anterolateral approach. The rates
of acetabular remodelling were similar for both protocols. Cite this article:
The October 2013 Knee Roundup360 looks at: Make it easy, release the MCL; Do patients remember clinical information in day surgery?; Osteoarthritis and arthroscopy?; How best to double your bundles; When to operate for infection; Cementless unicompartment knee replacement?; Tibial tubercle-trochlear groove confusion; Tarts, cherries and osteoarthritis
The October 2013 Hip &
Pelvis Roundup360 looks at: Young and impinging; Clothes, weather and femoral heads?; Go long, go cemented; Surgical repair of the abductors?; Aspirin for DVT prophylaxis?; Ceramic-on-polyethylene: a low-wear solution?; ALVAL and ASR™: the story continues….; Salvaging Legg-Calve-Perthes’ disease
Osteoarthritis results in changes in the dimensions
of the glenoid. This study aimed to assess the size and radius of curvature
of arthritic glenoids. A total of 145 CT scans were analysed, performed
as part of routine pre-operative assessment before total shoulder
replacement in 91 women and 54 men. Only patients with primary osteoarthritis and
a concentric glenoid were included in the study. The CT scans underwent
three-dimensional (3D) reconstruction and were analysed using dedicated
computer software. The measurements consisted of maximum superoinferior height,
anteroposterior width and a best-fit sphere radius of curvature
of the glenoid. The mean height was 40.2 mm ( With current shoulder replacement systems using a unique backside
radius of curvature for the glenoid component, there is a risk of
undertaking excessive reaming to adapt the bone to the component
resulting in sacrifice of subchondral bone or under-reaming and
instability of the component due to a ’rocking horse‘ phenomenon. Cite this article:
The June 2013 Knee Roundup360 looks at: iodine washout: chondrotoxic or antiseptic?; stem tip pain following revision knee replacements; metalwork removal prior to TKR; astroturf and ACL rupture; Robert Jones dressings; if thicker gloves safer; and the long leg radiograph: is it still the gold standard?