Objectives. The objective of this study was to compare the elution characteristics,
antimicrobial activity and mechanical properties of antibiotic-loaded
bone cement (ALBC) loaded with powdered antibiotic, powdered antibiotic
with inert filler (xylitol), or liquid antibiotic, particularly focusing
on vancomycin and amphotericin B. Methods. Cement specimens loaded with 2 g of vancomycin or amphotericin
B powder (powder group), 2 g of antibiotic powder and 2 g of xylitol
(xylitol group) or 12 ml of antibiotic solution containing 2 g of
antibiotic (liquid group) were tested. Results. Vancomycin elution was enhanced by 234% in the liquid group and
by 12% in the xylitol group compared with the powder group. Amphotericin
B elution was enhanced by 265% in the liquid group and by 65% in
the xylitol group compared with the powder group. Based on the disk-diffusion
assay, the eluate samples of vancomycin-loaded ALBC of the liquid group
exhibited a significantly larger inhibitory zone than samples of
the powder or the xylitol group. Regarding the ALBCs loaded with
amphotericin B, only the eluate samples of the liquid group exhibited
a clear inhibitory zone, which was not observed in either the xylitol
or the powder groups. The ultimate compressive strength was significantly
reduced in specimens containing liquid antibiotics. Conclusions. Adding vancomycin or amphotericin B antibiotic powder in distilled
water before mixing with bone cement can significantly improve the
efficiency of antibiotic release than can loading ALBC with the
same dose of antibiotic powder. This simple and effective method for
preparation of ALBCs can significantly improve the efficiency of
antibiotic release in ALBCs. Cite this article: Bone Joint
Objectives. To define Patient Acceptable Symptom State (PASS) thresholds
for the Oxford hip score (OHS) and Oxford knee score (OKS) at mid-term
follow-up. Methods. In a prospective multicentre cohort study, OHS and OKS were collected
at a mean follow-up of three years (1.5 to 6.0), combined with a
numeric rating scale (NRS) for satisfaction and an external validation
question assessing the patient’s willingness to undergo surgery
again. A total of 550 patients underwent total hip replacement (THR)
and 367 underwent total knee replacement (TKR). Results. Receiver operating characteristic (ROC) curves identified a PASS
threshold of 42 for the OHS after THR and 37 for the OKS after TKR.
THR patients with an OHS ≥ 42 and TKR patients with an OKS ≥ 37
had a higher NRS for satisfaction and a greater likelihood of being
willing to undergo surgery again. Conclusions. PASS thresholds appear larger at mid-term follow-up than at six
months after surgery. With- out external validation, we would advise
against using these PASS thresholds as absolute thresholds in defining
whether or not a patient has attained an acceptable symptom state
after THR or TKR. Cite this article: Bone Joint
Objective. The main object of this study was to use a geometric morphometric
approach to quantify the left-right symmetry of talus bones. . Methods. Analysis was carried out using CT scan images of 11 pairs of
intact tali. Two important geometric parameters, volume and surface
area, were quantified for left and right talus bones. The geometric
shape variations between the right and left talus bones were also
measured using deviation analysis. Furthermore, location of asymmetry
in the geometric shapes were identified. . Results. Numerical results showed that talus bones are bilaterally symmetrical
in nature, and the difference between the surface area of the left
and right talus bones was less than 7.5%. Similarly, the difference
in the volume of both bones was less than 7.5%. Results of the three-dimensional
(3D) deviation analyses demonstrated the mean deviation between
left and right talus bones were in the range of -0.74 mm to 0.62
mm. It was observed that in eight of 11 subjects, the deviation
in symmetry occurred in regions that are clinically less important
during talus surgery. . Conclusions. We conclude that left and right talus bones of intact human ankle
joints show a strong degree of symmetry. The results of this study
may have significance with respect to talus surgery, and in investigating
traumatic talus injury where the geometric shape of the contralateral
talus can be used as control. Cite this article: Bone Joint
The treatment of osteochondral lesions and osteoarthritis
remains an ongoing clinical challenge in orthopaedics. This review
examines the current research in the fields of cartilage regeneration,
osteochondral defect treatment, and biological joint resurfacing, and
reports on the results of clinical and pre-clinical studies. We
also report on novel treatment strategies and discuss their potential
promise or pitfalls. Current focus involves the use of a scaffold
providing mechanical support with the addition of chondrocytes or mesenchymal
stem cells (MSCs), or the use of cell homing to differentiate the
organism’s own endogenous cell sources into cartilage. This method
is usually performed with scaffolds that have been coated with a
chemotactic agent or with structures that support the sustained
release of growth factors or other chondroinductive agents. We also
discuss unique methods and designs for cell homing and scaffold
production, and improvements in biological joint resurfacing. There
have been a number of exciting new studies and techniques developed
that aim to repair or restore osteochondral lesions and to treat
larger defects or the entire articular surface. The concept of a
biological total joint replacement appears to have much potential. Cite this article: Bone Joint
Objectives. The purpose of this study was to refine an accepted contaminated
rat femur defect model to result in an infection rate of approximately
50%. This threshold will allow examination of treatments aimed at
reducing infection in open fractures with less risk of type II error. Methods . Defects were created in the stablised femurs of anaethetised
rats, contaminated with Staphylococcus aureus and
then debrided and irrigated six hours later. After 14 days, the
bone and implants were harvested for separate microbiological analysis.
This basic model was developed in several studies by varying the
quantity of bacterial inoculation, introducing various doses of
systemic antibiotics with and without local antibiotics. Results . The bacterial inoculation associated with a 50% infection rate
was established as 1 × 10. 2. colony forming units (CFU). With
an initial bacterial inoculum of 1 × 10. 5. CFU, the dose
of systemic antibiotics associated with 50% infection was 5 mg/Kg
of cafazolin injected sub-cutaneously every 12 hours, starting at
the time of the first debridment and continuing for 72 hours (seven
doses). The systemic dose of cafazolin was lowered to 2 mg/Kg when
antibiotic polymethyl methacrylate beads were used concurrently
with the same amount of bacterial inoculation. Conclusion. This model of open fracture infection has been further refined
with potential for local and systemic antibiotics. This is a versatile
model and with the concepts presented herein, it can be modified
to evaluate various emerging therapies and concepts for open fractures. Cite this article: Bone Joint
Objectives. Wear debris released from bearing surfaces has been shown to
provoke negative immune responses in the recipient. Excessive wear
has been linked to early failure of prostheses. Analysis using coordinate
measuring machines (CMMs) can provide estimates of total volumetric
material loss of explanted prostheses and can help to understand
device failure. The accuracy of volumetric testing has been debated,
with some investigators stating that only protocols involving hundreds
of thousands of measurement points are sufficient. We looked to
examine this assumption and to apply the findings to the clinical
arena. . Methods. We examined the effects on the calculated material loss from
a ceramic femoral head when different CMM scanning parameters were
used. Calculated wear volumes were compared with gold standard gravimetric
tests in a blinded study. . Results. Various scanning parameters including point pitch, maximum point
to point distance, the number of scanning contours or the total
number of points had no clinically relevant effect on volumetric
wear calculations. Gravimetric testing showed that material loss
can be calculated to provide clinically relevant degrees of accuracy. . Conclusions. Prosthetic surfaces can be analysed accurately and rapidly with
currently available technologies. Given these results, we believe
that routine analysis of explanted hip components would be a feasible
and logical extension to National Joint Registries. Cite this article: Bone Joint
Objectives. To conduct a pilot randomised controlled trial to evaluate the
feasibility of conducting a larger trial to evaluate the difference
in Victorian Institute of Sports Assessment-Achilles (VISA-A) scores
at six months between patients with Achilles tendinopathy treated
with a platelet-rich plasma (PRP) injection compared with an eccentric
loading programme. Methods. Two groups of patients with mid-substance Achilles tendinopathy
were randomised to receive a PRP injection or an eccentric loading
programme. A total of 20 patients were randomised, with a mean age
of 49 years (35 to 66). All outcome measures were recorded at baseline,
six weeks, three months and six months. Results. The mean VISA-A score for the injection group at the primary
endpoint of six months was 76.0 (95% confidence interval (CI) 58.3
to 93.7) and for the exercise group was 57.4 (95% CI 38.1 to 76.7).
There was no statistically significant difference between these
scores (p = 0.171), which was expected from such a pilot study. Conclusions. This pilot study has been key to providing data to inform a larger
study and shows that the methodology is feasible. Cite this article: Bone Joint
Objectives. Effects of insulin-like growth factor 1 (IGF1), fibroblast growth
factor 2 (FGF2) and bone morphogenetic protein 2 (BMP2) on the expression
of genes involved in the proliferation and differentiation of osteoblasts
in culture were analysed. The best sequence of growth factor addition
that induces expansion of cells before their differentiation was
sought. Methods. Primary human osteoblasts in in vitro culture
were treated with IGF1, BMP2 or FGF2 (10 ng/ml) for 24 hours (IGF1)
or 48 hours (BMP2 and FGF2). Experiments were performed during the
exponential growth phase with approximately 1e7 cells per 75 cm. 2. flask.
mRNA was reverse transcribed directly and analysed using RT-PCR
Taqman assays. Expression levels of key genes involved in cell growth
and differentiation (CDH11, TNFRSF11B, RUNX2, POSTN, ALP, WNT5A,
LEF1, HSPA5, FOS, p21) were monitored using RT-PCR with gene-specific
Taqman probes. . Results. Autocrine expression of BMP2 is stimulated by FGF2 and BMP2 itself.
BMP2 and FGF2 act as proliferative factors as indicated by reduced
expression of ALP and POSTN, whereas IGF1 exhibits a more subtle
picture: the Wingless und Int-1 (Wnt) signalling pathway and the
Smad pathway, but not p38 mitogen-activated protein (MAP) kinase signalling,
were shown to be activated by IGF1, leading to proliferation and
differentiation of the cells. . Conclusions. For future use of autologous bone cells in the management of
bony defects, new treatment options take advantage of growth factors
and differentiation factors. Thus, our results might help to guide
the timely application of these factors for the expansion and subsequent
differentiation of osteoblastic cells in culture. Cite this article: Bone Joint
Objectives. The most concerning infection of allografts and operative procedures
is methicillin resistant Staphylococcus aureus (MRSA)
and no current iontophoresed antibiotics effectively combat this
microbe. It was initially hypothesised that iontophoresis of vancomycin
through bone would not be effective due to its large molecular size
and lack of charge. The aim of this study was to determine whether
this was a viable procedure and to find the optimum conditions for its
use. . Methods. An iontophoresis cell was set up with varying concentrations
of Vancomycin within the medulla of a section of sheep tibia, sealed
from an external saline solution. The cell was run for varying times,
Vancomycin concentrations and voltages, to gain information on optimisation
of conditions for impregnating the graft. Each graft was then sectioned
and dust ground from the exposed surface. The dust was serially
washed to extract the Vancomycin and concentrations measured and
plotted for all variables tested. Results. Vancomycin was successfully delivered and impregnated to the
graft using the iontophoresis technique. The first order fit to
the whole data set gave a significant result (p = 0.0233), with
a significant concentration (p = 0.02774) component. The time component
was the next most significant (p = 0.0597), but did not exceed the
95% confidence level. Conclusions. Iontophoresis is an effective method for delivering Vancomycin
to allograft bone. The concentrations of the vancomycin solution
affected the bone concentration, but results were highly variable.
Further study should be done on the effectiveness of delivering
different antibiotics using this method. Cite this article: Bone
Joint
Objectives . The objective of this study is to determine an optimal antibiotic-loaded
bone cement (ALBC) for infection prophylaxis in total joint arthroplasty
(TJA). Methods. We evaluated the antibacterial effects of polymethylmethacrylate
(PMMA) bone cements loaded with vancomycin, teicoplanin, ceftazidime,
imipenem, piperacillin, gentamicin, and tobramycin against methicillin-sensitive Staphylococcus
aureus (MSSA), methicillin-resistant Staph. aureus (MRSA),
coagulase-negative staphylococci (CoNS), Escherichia
coli, Pseudomonas aeruginosa, and Klebsiella
pneumoniae. Standardised cement specimens made from 40 g
PMMA loaded with 1 g antibiotics were tested for elution characteristics,
antibacterial activities, and compressive strength in vitro. . Results. The ALBC containing gentamicin provided a much longer duration
of antibiotic release than those containing other antibiotic. Imipenem-loading
on the cement had a significant adverse effect on the compressive
strength of the ALBC, which made it insufficient for use in prosthesis
fixation. All of the tested antibiotics maintained their antibacterial
properties after being mixed with PMMA. The gentamicin-loaded ALBC
provided a broad antibacterial spectrum against all the test organisms
and had the greatest duration of antibacterial activity against
MSSA, CoNS, P. aeruginosa and E. coli. . Conclusion. When considering the use of ALBC as infection prophylaxis in
TJA, gentamicin-loaded ALBC may be a very effective choice. Cite this article: Bone Joint
Objectives . The effects of disease progression and common tendinopathy treatments
on the tissue characteristics of human rotator cuff tendons have
not previously been evaluated in detail owing to a lack of suitable
sampling techniques. This study evaluated the structural characteristics
of torn human supraspinatus tendons across the full disease spectrum,
and the short-term effects of subacromial corticosteroid injections
(SCIs) and subacromial decompression (SAD) surgery on these structural
characteristics. . Methods . Samples were collected inter-operatively from supraspinatus tendons
containing small, medium, large and massive full thickness tears
(n = 33). Using a novel minimally invasive biopsy technique, paired
samples were also collected from supraspinatus tendons containing
partial thickness tears either before and seven weeks after subacromial
SCI (n = 11), or before and seven weeks after SAD surgery (n = 14).
Macroscopically normal subscapularis tendons of older patients (n
= 5, mean age = 74.6 years) and supraspinatus tendons of younger
patients (n = 16, mean age = 23.3) served as controls. Ultra- and
micro-structural characteristics were assessed using atomic force
microscopy and polarised light microscopy respectively. . Results. Significant structural differences existed between torn and control
groups. Differences were identifiable early in the disease spectrum,
and increased with increasing tear size. Neither SCI nor SAD surgery
altered the structural properties of partially torn tendons seven
weeks after treatment. . Conclusions . These findings may suggest the need for early clinical intervention
strategies for torn rotator cuff tendons in order to prevent further
degeneration of the tissue as tear size increases. Further work
is required to establish the long-term abilities of SCI and SAD
to prevent, and even reverse, such degeneration. Cite this article: Bone Joint
Objectives. To study the measurement properties of a joint specific patient
reported outcome measure, a measure of capability and a general
health-related quality of life (HRQOL) tool in a large cohort of
patients with a hip fracture. Methods. Responsiveness and associations between the Oxford Hip Score
(a hip specific measure: OHS), ICEpop CAPability (a measure of capability
in older people: ICECAP-O) and EuroQol EQ-5D (general health-related
quality of life measure: EQ-5D) were assessed using data available
from two large prospective studies. The three outcome measures were assessed
concurrently at a number of fixed follow-up time-points in a consecutive
sequence of patients, allowing direct assessment of change from
baseline, inter-measure associations and validity using a range
of statistical methods. Results. ICECAP-O was not responsive to change. EQ-5D was responsive to
change from baseline, with an estimated standardised effect size
for the two datasets of 0.676 and 0.644 at six weeks and four weeks
respectively; this was almost as responsive to change as OHS (1.14 at
four weeks). EQ-5D correlated strongly with OHS; Pearson correlation
coefficients were 0.74, 0.77 and 0.70 at baseline, four weeks and
four months. EQ-5D is a moderately good predictor of death at 12
months following hip fracture. Furthermore, EQ-5D reported by proxies
(relatives and carers) behaves similarly to self-reported scores. Conclusions. Our findings suggest that a general HRQOL tool such as EQ-5D
could be used to measure outcome for patients recovering from hip
fracture, including those with cognitive impairment. Cite this article: Bone Joint
Objectives. Metal-on-metal hip resurfacing (MOMHR) is available as an alternative
option for younger, more active patients. There are failure modes
that are unique to MOMHR, which include loosening of the femoral
head and fractures of the femoral neck. Previous studies have speculated
that changes in the vascularity of the femoral head may contribute
to these failure modes. This study compares the survivorship between
the standard posterior approach (SPA) and modified posterior approach
(MPA) in MOMHR. . Methods. A retrospective clinical outcomes study was performed examining
351 hips (279 male, 72 female) replaced with Birmingham Hip Resurfacing
(BHR, Smith and Nephew, Memphis, Tennessee) in 313 patients with
a pre-operative diagnosis of osteoarthritis. The mean follow-up
period for the SPA group was 2.8 years (0.1 to 6.1) and for the
MPA, 2.2 years (0.03 to 5.2); this difference in follow-up period
was statistically significant (p <
0.01). Survival analysis was
completed using the Kaplan–Meier method. . Results. At four years, the Kaplan–Meier survival curve for the SPA was
97.2% and 99.4% for the MPA; this was statistically significant
(log-rank; p = 0.036). There were eight failures in the SPA and
two in the MPA. There was a 3.5% incidence of femoral head collapse
or loosening in the SPA and 0.4% in the MPA, which represented a
significant difference (p = 0.041). There was a 1.7% incidence of
fractures of the femoral neck in the SPA and none in the MPA (p
= 0.108). . Conclusion. This study found a significant difference in survivorship at
four years between the SPA and the MPA (p = 0.036). The clinical
outcomes of this study suggest that preserving the vascularity of
the femoral neck by using the MPA results in fewer vascular-related
failures in MOMHRs. Cite this article: Bone Joint
Introduction. Osteoarthritis (OA) is a progressively debilitating disease that
affects mostly cartilage, with associated changes in the bone. The
increasing incidence of OA and an ageing population, coupled with
insufficient therapeutic choices, has led to focus on the potential
of stem cells as a novel strategy for cartilage repair. Methods. In this study, we used scaffold-free mesenchymal stem cells (MSCs)
obtained from bone marrow in an experimental animal model of OA
by direct intra-articular injection. MSCs were isolated from 2.8
kg white New Zealand rabbits. There were ten in the study group
and ten in the control group. OA was induced by unilateral transection
of the anterior cruciate ligament of the knee joint. At 12 weeks
post-operatively, a single dose of 1 million cells suspended in 1 ml
of medium was delivered to the injured knee by direct intra-articular
injection. The control group received 1 ml of medium without cells.
The knees were examined at 16 and 20 weeks following surgery. Repair
was investigated radiologically, grossly and histologically using
haematoxylin and eosin, Safranin-O and toluidine blue staining. Results. Radiological assessment confirmed development of OA changes after
12 weeks. Rabbits receiving MSCs showed a lower degree of cartilage
degeneration, osteophyte formation, and subchondral sclerosis than
the control group at 20 weeks post-operatively. The quality of cartilage
was significantly better in the cell-treated group compared with the
control group after 20 weeks. Conclusions. Bone marrow-derived MSCs could be promising cell sources for
the treatment of OA. Neither stem cell culture nor scaffolds are
absolutely necessary for a favourable outcome. Cite this article: Bone Joint
Objectives. We performed in vitro validation
of a non-invasive skin-mounted system that could allow quantification
of anteroposterior (AP) laxity in the outpatient setting. Methods. A total of 12 cadaveric lower limbs were tested with a commercial
image-free navigation system using trackers secured by bone screws.
We then tested a non-invasive fabric-strap system. The lower limb
was secured at 10° intervals from 0° to 60° of knee flexion and
100 N of force was applied perpendicular to the tibia. Acceptable
coefficient of repeatability (CR) and limits of agreement (LOA)
of 3 mm were set based on diagnostic criteria for anterior cruciate
ligament (ACL) insufficiency. Results. Reliability and precision within the individual invasive and
non-invasive systems was acceptable throughout the range of flexion
tested (intra-class correlation coefficient 0.88, CR 1.6 mm). Agreement
between the two systems was acceptable measuring AP laxity between
full extension and 40° knee flexion (LOA 2.9 mm). Beyond 40° of
flexion, agreement between the systems was unacceptable (LOA >
3
mm). Conclusions. These results indicate that from full knee extension to 40° flexion,
non-invasive navigation-based quantification of AP tibial translation
is as accurate as the standard validated commercial system, particularly
in the clinically and functionally important range of 20° to 30°
knee flexion. This could be useful in diagnosis and post-operative
evaluation of ACL pathology. Cite this article: Bone Joint
Objectives. The goals of this study were: 1) to determine if high-fat diet
(HFD) feeding in female mice would negatively impact biomechanical
and histologic consequences on the Achilles tendon and quadriceps
muscle; and 2) to investigate whether exercise and branched-chain
amino acid (BCAA) supplementation would affect these parameters
or attenuate any negative consequences resulting from HFD consumption. Methods. We examined the effects of 16 weeks of 60% HFD feeding, voluntary
exercise (free choice wheel running) and BCAA administration in
female C57BL/6 mice. The Achilles tendons and quadriceps muscles
were removed at the end of the experiment and assessed histologically
and biomechanically. Results. HFD feeding significantly decreased the Achilles tendon modulus
without histological alterations. BCAA administration significantly
decreased the stiffness of Achilles tendons in the exercised normal
diet mice. Exercise partially ameliorated both the weight gain and
glucose levels in the HFD-fed mice, led to a significant decrease
in the maximum load of the Achilles tendon, and an increase in the
average fibril diameter of the quadriceps femoris muscle. There
were significant correlations between body weight and several biomechanical
properties, demonstrating the importance of controlling obesity
for maintaining healthy tendon properties. . Conclusions. In summary, this study showed a significant impact of obesity
and body weight on tendon biomechanical properties with limited
effects of exercise and BCAAs. Cite this article: Bone Joint
Objectives. An experimental piglet model induces avascular necrosis (AVN)
and deformation of the femoral head but its secondary effects on
the developing acetabulum have not been studied. The aim of this
study was to assess the development of secondary acetabular deformation
following femoral head ischemia. Methods. Intracapsular circumferential ligation at the base of the femoral
neck and sectioning of the ligamentum teres were performed in three
week old piglets. MRI was then used for qualitative and quantitative
studies of the acetabula in operated and non-operated hips in eight
piglets from 48 hours to eight weeks post-surgery. Specimen photographs and
histological sections of the acetabula were done at the end of the
study. . Results. The operated-side acetabula were wider, shallower and misshapen,
with flattened labral edges. At eight weeks, increased acetabular
cartilage thickness characterised the operated sides compared with
non-operated sides (p <
0.001, ANOVA). The mean acetabular width
on the operated side was increased (p = 0.015) while acetabular depth
was decreased anteriorly (p = 0.007) and posteriorly (p = 0.44).
The cartilage was thicker, with delayed acetabular bone formation,
and showed increased vascularisation with fibrosis laterally and
focal degenerative changes involving chondrocyte hypocellularity,
chondrocyte cloning, peripheral pannus formation and surface fibrillation. . Conclusions. We demonstrate that femoral head AVN in the young growing piglet
also induced, and was coupled with, secondary malformation in acetabular
shape affecting both articular and adjacent pelvic cartilage structure,
and acetabular bone. The femoral head model inducing AVN can also
be applied to studies of acetabular maldevelopment, which is less
well understood in terms of developing hip malformation. Cite this article: Bone Joint
Objective. Mortality rates reported by the National Joint Registry for England
and Wales (NJR) were higher following cemented total knee replacement
(TKR) compared with uncemented procedures. The aim of this study
is to examine and compare the effects of cemented and uncemented
TKR on the activation of selected markers of inflammation, endothelium,
and coagulation, and on the activation of selected cytokines involved
in the various aspects of the systemic response following surgery. Methods. This was a single centre, prospective, case-control study. Following
enrolment, blood samples were taken pre-operatively, and further
samples were collected at day one and day seven post-operatively.
One patient in the cemented group developed a deep-vein thrombosis
confirmed on ultrasonography and was excluded, leaving 19 patients
in this cohort (mean age 67.4, (. sd. 10.62)), and one patient
in the uncemented group developed a post-operative wound infection
and was excluded, leaving 19 patients (mean age 66.5, (. sd. 7.82)). Results. Both groups had a similar response with regards to the levels
of C-reactive protein (CRP), interleukin 6 (IL-6) and tumour necrosis
factor-alpha (TNFα). CD40 levels rose significantly on the cemented
group over day one to day seven compared with that of the uncemented
group, which occurred over the first 24 hours. The CD14/42a levels demonstrated
a statistically significant increase in the cemented group (p <
0.001 first 24 hours and p = 0.02 between days one and seven). . Conclusions. The uncemented and cemented groups demonstrated significant changes
in the various parameters measured at various time points but apart
from CD14/42a levels, there was no significant difference in the
serum markers of inflammation, coagulation and endothelial dysfunction
following cemented TKR. Cite this article: Bone Joint
Objectives. Although many clinical and experimental investigations have shed
light on muscle atrophy and intramuscular accumulation of fat after
rotator cuff disruption, none have reported on their onset in the
absence of muscle retraction. Methods. In 30 rabbits, we detached one supraspinatus (SSP) tendon and
repaired it immediately, thus preventing muscle retraction. The
animals were killed in groups of 10 at one, two and six weeks. Both
shoulders of 15 non-operated rabbits served as controls. We measured
the weight and volume of SSP muscles and quantified the cross-sectional
area of intramuscular fat (i-fat) histologically. Results. There was significant loss of muscle weight and volume after
one week (p = 0.004 and 0.003, respectively), and two weeks (both
p <
0.001) in the experimental group; which recovered to control
values after six weeks. I-fat accumulated one week after immediate repair,
greater than in the control group and statistically significant
at the mid-part of the muscle (mean 2.7% vs 1.5%,
p = 0.008). I-fat continued to accumulate up to six weeks at all sites
of the SSP muscle (all 3, p <
0.001). More fat accumulated closer
to the musculotendinous junction than at the mid-part after two
and six weeks (p = 0.012 and 0.019, respectively). Conclusion. Muscle atrophy and i-fat accumulation occur early after SSP tendon
tear and immediate repair. While early repair benefitted muscle
recovery, it did not prevent fat accumulation. SSP muscle retraction
was not essential to the muscle alterations. The divergent evolution
of muscle and fat points to different pathophysiologies. Cite this article: Bone Joint
Objectives. There are several reports clarifying successful results following
open reduction using Ludloff’s medial approach for congenital (CDH)
or developmental dislocation of the hip (DDH). This study aimed
to reveal the long-term post-operative course until the period of
hip-joint maturity after the conventional surgical treatments. Methods. A long-term follow-up beyond the age of hip-joint maturity was
performed for 115 hips in 103 patients who underwent open reduction
using Ludloff’s medial approach in our hospital. The mean age at
surgery was 8.5 months (2 to 26) and the mean follow-up was 20.3
years (15 to 28). The radiological condition at full growth of the hip
joint was evaluated by Severin’s classification. Results. All 115 hips successfully attained reduction after surgery; however,
74 hips (64.3%) required corrective surgery at a mean age of 2.6
years (one to six). According to Severin’s classification, 69 hips
(60.0%) were classified as group I or II, which were considered
to represent acceptable results. A total of 39 hips (33.9%) were
group III and the remaining seven hips (6.1%) group IV. As to re-operation,
20 of 21 patients who underwent surgical reduction after 12 months
of age required additional corrective surgeries during the growth
period as the hip joint tended to subluxate gradually. Conclusion. Open reduction using Ludloff’s medial approach accomplished successful
joint reduction for persistent CDH or DDH, but this surgical treatment
was only appropriate before the ambulating stage. Cite this article: Bone Joint
