The contraindications for unicompartmental knee replacement (UKR) remain controversial. The views of many surgeons are based on Kozinn and Scott’s 1989 publication which stated that patients who weighed more than 82 kg, were younger than 60 years, undertook heavy labour, had exposed bone in the patellofemoral joint or chondrocalcinosis, were not ideal candidates for UKR. Our aim was to determine whether these potential contraindications should apply to patients with a mobile-bearing UKR. In order to do this the outcome of patients with these potential contraindications was compared with that of patients without the contraindications in a prospective series of 1000 UKRs. The outcome was assessed using the Oxford knee score, the American Knee Society score, the Tegner activity score, revision rate and survival. The clinical outcome of patients with each of the potential contraindications was similar to or better than those without each contraindication. Overall, 678 UKRs (68%) were performed in patients who had at least one potential contraindication and only 322 (32%) in patients deemed to be ideal. The survival at ten years was 97.0% (95% confidence interval 93.4 to 100.0) for those with potential contraindications and 93.6% (95% confidence interval 87.2 to 100.0) in the ideal patients. We conclude that the thresholds proposed by Kozinn and Scott using weight, age, activity, the state of the patellofemoral joint and chondrocalcinosis should not be considered to be contraindications for the use of the Oxford UKR.
A total of 92 patients with symptoms for over
six months due to subacromial impingement of the shoulder, who were
being treated with physiotherapy, were included in this study. While
continuing with physiotherapy they waited a further six months for
surgery. They were divided into three groups based on the following
four clinical and radiological criteria: temporary benefit following
steroid injection, pain in the mid-arc of abduction, a consistently positive
Hawkins test and radiological evidence of impingement. Group A fulfilled
all four criteria, group B three criteria and group C two criteria.
A total of nine patients improved while waiting for surgery and
were excluded, leaving 83 who underwent arthroscopic subacromial
decompression (SAD). The new Oxford shoulder score was recorded
pre-operatively and at three and 12 months post-operatively. A total of 51 patients (group A) had a significant improvement
in the mean shoulder score from 18 (13 to 22) pre-operatively to
38 (35 to 42) at three months (p <
0.001). The mean score in
this group was significantly better than in group B (21 patients)
and C (11 patients) at this time. At one year patients in all groups
showed improvement in scores, but patients in group A had a higher
mean score (p = 0.01). At one year patients in groups A and B did
better than those in group C (p = 0.01). Arthroscopic SAD is a beneficial intervention in selected patients.
The four criteria could help identify patients in whom it is likely
to be most effective.
We carried out a cross-sectional study with analysis of the demographic, clinical and laboratory characteristics of patients with metal-on-metal hip resurfacing, ceramic-on-ceramic and metal-on-polyethylene hip replacements. Our aim was to evaluate the relationship between metal-on-metal replacements, the levels of cobalt and chromium ions in whole blood and the absolute numbers of circulating lymphocytes. We recruited 164 patients (101 men and 63 women) with hip replacements, 106 with metal-on-metal hips and 58 with non-metal-on-metal hips, aged <
65 years, with a pre-operative diagnosis of osteoarthritis and no pre-existing immunological disorders. Laboratory-defined T-cell lymphopenia was present in13 patients (15%) (CD8+ lymphopenia) and 11 patients (13%) (CD3+ lymphopenia) with unilateral metal-on-metal hips. There were significant differences in the absolute CD8+ lymphocyte subset counts for the metal-on-metal groups compared with each control group (p-values ranging between 0.024 and 0.046). Statistical modelling with analysis of covariance using age, gender, type of hip replacement, smoking and circulating metal ion levels, showed that circulating levels of metal ions, especially cobalt, explained the variation in absolute lymphocyte counts for almost all lymphocyte subsets.
Autologous chondrocyte implantation is an established method of treatment for symptomatic articular defects of cartilage. Clinically, all the patients improved significantly. Patients with lesions larger than 3 cm2 improved significantly more than those with smaller lesions. There was no correlation between the clinical outcome and the body mass index, age, duration of symptoms and location of the defects. The mean arthroscopic International Cartilage Repair Society score was 10 (5 to 12) of a maximum of 12. Predominantly hyaline cartilage was seen in eight of the 13 patients (62%) who had follow-up biopsies. Our findings suggest that autologous chondrocyte implantation in combination with a novel hydrogel results in a significant clinical improvement at follow-up at two years, more so for larger and deeper lesions. The surgical procedure is uncomplicated, and predominantly hyaline cartilage-like repair tissue was observed in eight patients.
We prospectively followed 191 consecutive collarless
polished tapered (CPT) femoral stems, implanted in 175 patients
who had a mean age at operation of 64.5 years (21 to 85). At a mean
follow-up of 15.9 years (14 to 17.5), 86 patients (95 hips) were
still alive. The fate of all original stems is known. The 16-year
survivorship with re-operation for any reason was 80.7% (95% confidence
interval 72 to 89.4). There was no loss to follow-up, with clinical
data available on all 95 hips and radiological assessment performed
on 90 hips (95%). At latest follow-up, the mean Harris hip score
was 78 (28 to 100) and the mean Oxford hip score was 36 (15 to 48).
Stems subsided within the cement mantle, with a mean subsidence
of 2.1 mm (0.4 to 19.2). Among the original cohort, only one stem
(0.5%) has been revised due to aseptic loosening. In total seven
stems were revised for any cause, of which four revisions were required
for infection following revision of the acetabular component. A
total of 21 patients (11%) required some sort of revision procedure;
all except three of these resulted from failure of the acetabular
component. Cemented acetabular components had a significantly lower
revision burden (three hips, 2.7%) than Harris Galante uncemented
components (17 hips, 21.8%) (p <
0.001). The CPT stem continues to provide excellent radiological and
clinical outcomes at 15 years following implantation. Its results
are consistent with other polished tapered stem designs.
We carried out a prospective randomised study designed to compare the penetration rate of acetabular polyethylene inserts of identical design but different levels of cross-linking at a minimum of four years follow-up. A total of 102 patients (102 hips) were randomised to receive either highly cross-linked Durasul, or contemporary Sulene polyethylene inserts at total hip replacement. A single blinded observer used the Martell system to assess penetration of the femoral head. At a mean follow-up of 4.9 years (4.2 to 6.1) the mean femoral head penetration rate was 0.025 mm/year (
We have previously described the mid- to long-term
results of conventional simple varus intertrochanteric osteotomy
for osteonecrosis of the femoral head, showing that 19 of the 26
hips had good or excellent results. We extended the follow-up to
a mean of 18.1 years (10.5 to 26) including a total of 34 hips in
28 patients, with a mean age at surgery of 33 years (19 to 53).
There were 18 men and ten women and 25 hips (74%) had a satisfactory
result with a Harris hip score ≥ 80. In all, six hips needed total
hip replacement (THR) or hemiarthroplasty. The collapse of the femoral
head or narrowing of the joint space was found to have progressed
in nine hips (26%). Leg shortening after osteotomy was a mean of
19 mm (8 to 36). With conversion to THR or hemiarthroplasty as the
endpoint, the ten-year survival rate was 88.2% (95% confidence interval
(CI) 82.7 to 93.7) and the 20-year survival rate was 79.7% (95%
CI 72.1 to 87.3); four hips were converted at ten years and other
two hips were converted at 20 years. Shortening of the leg after osteotomy remains a concern; however,
the conventional varus half-wedge osteotomy provides favourable
long-term results in hips with less than two-thirds of the medial
part of the femoral head affected by necrotic bone and with normal
bone superolaterally.
We carried out a blinded prospective randomised controlled trial comparing 2-octylcyanoacrylate (OCA), subcuticular suture (monocryl) and skin staples for skin closure following total hip and total knee arthroplasty. We included 102 hip replacements and 85 of the knee. OCA was associated with less wound discharge in the first 24 hours for both the hip and the knee. However, with total knee replacement there was a trend for a more prolonged wound discharge with OCA. With total hip replacement there was no significant difference between the groups for either early or late complications. Closure of the wound with skin staples was significantly faster than with OCA or suture. There was no significant difference in the length of stay in hospital, Hollander wound evaluation score (cosmesis) or patient satisfaction between the groups at six weeks for either hips or knees. We consider that skin staples are the skin closure of choice for both hip and knee replacements.
In an interdisciplinary project involving electronic
engineers and clinicians, a telemetric system was developed to measure
the bending load in a titanium internal femoral fixator. As this
was a new device, the main question posed was: what clinically relevant
information could be drawn from its application? As a first clinical
investigation, 27 patients (24 men, three women) with a mean age
of 38.4 years (19 to 66) with femoral nonunions were treated using the
system. The mean duration of the nonunion was 15.4 months (5 to
69). The elasticity of the plate-callus system was measured telemetrically
until union. Conventional radiographs and a CT scan at 12 weeks
were performed routinely, and healing was staged according to the
CT scans. All nonunions healed at a mean of 21.5 weeks (13 to 37).
Well before any radiological signs of healing could be detected,
a substantial decrease in elasticity was recorded. The relative
elasticity decreased to 50% at a mean of 7.8 weeks (3.5 to 13) and
to 10% at a mean of 19.3 weeks (4.5 to 37). At 12 weeks the mean
relative elasticity was 28.1% (0% to 56%). The relative elasticity
was significantly different between the different healing stages
as determined by the CT scans. Incorporating load measuring electronics into implants is a promising
option for the assessment of bone healing. Future application might
lead to a reduction in the need for exposure to ionising radiation
to monitor fracture healing.
In patients with traumatic brain injury and fractures
of long bones, it is often clinically observed that the rate of bone
healing and extent of callus formation are increased. However, the
evidence has been unconvincing and an association between such an
injury and enhanced fracture healing remains unclear. We performed
a retrospective cohort study of 74 young adult patients with a mean
age of 24.2 years (16 to 40) who sustained a femoral shaft fracture
(AO/OTA type 32A or 32B) with or without a brain injury. All the
fractures were treated with closed intramedullary nailing. The main
outcome measures included the time required for bridging callus
formation (BCF) and the mean callus thickness (MCT) at the final
follow-up. Comparative analyses were made between the 20 patients
with a brain injury and the 54 without brain injury. Subgroup comparisons
were performed among the patients with a brain injury in terms of
the severity of head injury, the types of intracranial haemorrhage
and gender. Patients with a brain injury had an earlier appearance
of BCF
(p <
0.001) and a greater final MCT value (p <
0.001) than
those without. There were no significant differences with respect
to the time required for BCF and final MCT values in terms of the
severity of head injury (p = 0.521 and p = 0.153, respectively),
the types of intracranial haemorrhage (p = 0.308 and p = 0.189,
respectively) and gender (p = 0.383 and
p = 0.662, respectively). These results confirm that an injury to the brain may be associated
with accelerated fracture healing and enhanced callus formation.
However, the severity of the injury to the brain, the type of intracranial
haemorrhage and gender were not statistically significant factors
in predicting the rate of bone healing and extent of final callus formation.
The ideal bearing surface for young patients
undergoing total hip replacement (THR) remains controversial. We report
the five-year results of a randomised controlled trial comparing
the clinical and radiological outcomes of 102 THRs in 91 patients
who were <
65 years of age. These patients were randomised to
receive a cobalt–chrome on ultra-high-molecular-weight polyethylene,
cobalt–chrome on highly cross-linked polyethylene, or a ceramic-on-ceramic
bearing. In all, 97 hip replacements in 87 patients were available
for review at five years. Two hips had been revised, one for infection
and one for peri-prosthetic fracture. At the final follow-up there were no significant differences
between the groups for the mean Western Ontario and McMaster Universities
osteoarthritis index (pain, p = 0.543; function, p = 0.10; stiffness,
p = 0.99), Short Form-12 (physical component, p = 0.878; mental
component, p = 0.818) or Harris hip scores (p = 0.22). Radiological
outcomes revealed no significant wear in the ceramic group. Comparison of standard and highly cross-linked polyethylene,
however, revealed an almost threefold difference in the mean annual
linear wear rates (0.151 mm/year
There is no diagnostic, non-invasive method for the early detection of loosening after total hip arthroplasty. In a pilot study, we have analysed two serum markers of bone remodelling, procollagen I C-terminal extension peptide (PICP) and cross-linked N-terminal telopeptide (NTx), as well as the diagnostic performance of NTx for the assessment of osteolysis. We recruited 21 patients with loosening (group I), 18 with a well-fixed prosthesis (group II) and 17 at the time of primary arthroplasty for osteoarthritis (OA) (group III). Internal normal reference ranges were obtained from 30 healthy subjects (group IV). The serum PICP level was found to be significantly lower in patients with OA and those with loosening, when compared with those with stable implants, while the NTx level was significantly increased only in the group with loosening, suggesting that collagen degradation depended on the altered bone turnover induced by the implant. This hypothesis was reinforced by the finding that the values in the pre-surgery patients and stable subjects were comparable with the reference range of younger healthy subjects. A high specificity and positive predictive value for NTx provided good diagnostic evidence of agreement between the test and the clinical and radiological evaluations. The NTx level could be used to indicate stability of the implant. However, further prospective, larger studies are necessary.
To investigate the differences of open reduction and internal
fixation (ORIF) of complex AO Type C distal radius fractures between
two different models of a single implant type. A total of 136 patients who received either a 2.4 mm (n = 61)
or 3.5 mm (n = 75) distal radius locking compression plate (LCP
DR) using a volar approach were followed over two years. The main
outcome measurements included motion, grip strength, pain, and the
scores of Gartland and Werley, the Short-Form 36 (SF-36) and the
Disabilities of the Arm, Shoulder, and Hand (DASH). Differences
between the treatment groups were evaluated using regression analysis
and the likelihood ratio test with significance based on the Bonferroni
corrected p-value of <
0.003.Objectives
Methods
Patient expectations and their fulfilment are
an important factor in determining patient-reported outcome and satisfaction
of hip (THR) and knee replacement (TKR). The aim of this prospective
cohort study was to examine the expectations of patients undergoing
THR and TKR, and to identify differences in expectations, predictors
of high expectations and the relationship between the fulfilment
of expectations and patient-reported outcome measures. During the
study period, patients who underwent 346 THRs and 323 TKRs completed
an expectation questionnaire, Oxford score and Short-Form 12 (SF-12)
score pre-operatively. At one year post-operatively, the Oxford
score, SF-12, patient satisfaction and expectation fulfilment were
assessed. Univariable and multivariable analysis were performed.
Improvements in mobility and daytime pain were the most important
expectations in both groups. Expectation level did not differ between
THR and TKR. Poor Oxford score, younger age and male gender significantly
predicted high pre-operative expectations (p <
0.001). The level
of pre-operative expectation was not significantly associated with
the fulfilment of expectations or outcome. THR better met the expectations
identified as important by patients. TKR failed to meet expectations
of kneeling, squatting and stair climbing. High fulfilment of expectation
in both THR and TKR was significantly predicted by young age, greater
improvements in Oxford score and high pre-operative mental health
scores. The fulfilment of expectations was highly correlated with satisfaction.
Filling the empty holes in peri-articular locking
plates may improve the fatigue strength of the fixation. The purpose of
this A locking/compression plate was applied to 33 synthetic femurs
and then a 6 cm metaphyseal defect was created (AO Type 33-A3).
The specimens were then divided into three groups: unplugged, plugged
with locking screw only and fully plugged holes. They were then
tested using a stepwise or run-out fatigue protocol, each applying
cyclic physiological multiaxial loads. All specimens in the stepwise group failed at the 770 N load
level. The mean number of cycles to failure for the stepwise specimen
was 25 500 cycles ( In conclusion, filling the empty combination locking/compression
holes in peri-articular distal femur locking plates at the level
of supracondylar comminution does not increase the fatigue life
of the fixation in a comminuted supracondylar femoral fracture model
(AO 33-A3) with a 6 cm gap.
The low contact stress patellofemoral replacement consists of a trochlear component and a modular patellar component which has a metal-backed mobile polyethylene bearing. We present the early results of the use of this prosthesis for established isolated patellofemoral arthritis in 51 consecutive patellofemoral replacements in 35 patients. The mean follow-up was 25 months (5 to 60). The estimated survival rate at three years was 63% (95% confidence interval 47 to 80) with revision as the endpoint and 46% (95% confidence interval 30 to 63) with revision and ongoing moderate or severe pain as the endpoint. The early results of the use of the low contact stress patellofemoral replacement are disappointing with a high rate of revision. We cannot therefore recommend its use.
Patella subluxation assessed on dynamic MRI has
previously been shown to be associated with anterior knee pain. In
this MRI study of 60 patients we investigated the relationship between
subluxation and multiple bony, cartilaginous and soft-tissue factors
that might predispose to subluxation using discriminant function
analysis. Patella engagement (% of patella cartilage overlapping with trochlea
cartilage) had the strongest relationship with subluxation. Patellae
with >
30% engagement tended not to sublux; those with <
30%
tended to sublux. Other factors that were associated with subluxation
included the tibial tubercle-trochlea notch distance, vastus medialis obliquus
distance from patella, patella alta, and the bony and cartilaginous
sulcus angles in the superior part of the trochlea. No relationship
was found between subluxation and sulcus angles for cartilage and
bone in the middle and lower part of the trochlea, cartilage thicknesses
and Wiberg classification of the patella. This study indicates that patella engagement is a key factor
associated with patellar subluxation. This suggests that in patients
with anterior knee pain with subluxation, resistant to conservative
management, surgery directed towards improving patella engagement
should be considered. A clinical trial is necessary to test this
hypothesis.
We report the results of 79 patients (81 hips)
who underwent impaction grafting at revision hip replacement using the
Exeter femoral stem. Their mean age was 64 years (31 to 83). According
to the Endoklinik classification, 20 hips had a type 2 bone defect,
40 had type 3, and 21 had type 4. The mean follow-up for unrevised
stems was 10.4 years (5 to 17). There were 12 re-operations due to intra- and post-operative
fractures, infection (one hip) and aseptic loosening (one hip).
All re-operations affected type 3 (6 hips) and 4 (6 hips) bone defects.
The survival rate for re-operation for any cause was 100% for type
2, 81.2% (95% confidence interval (CI) 67.1 to 95.3) for type 3,
and 70.8% (95% CI 51.1 to 90.5) for type 4 defects at 14 years.
The survival rate with further revision for aseptic loosening as
the end point was 98.6% (95% CI 95.8 to 100). The final clinical
score was higher for patients with type 2 bone defects than type
4 regarding pain, function and range of movement. Limp was most
frequent in the type 4 group (p <
0.001). The mean subsidence
of the stem was 2.3 mm ( The impacted bone grafting technique has good clinical results
in femoral revision. However, major bone defects affect clinical
outcome and also result in more operative complications.
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.
The scarcity of mesenchymal stem cells (MSCs) in iliac crest bone marrow aspirate (ICBMA), and the expense and time in culturing cells, has led to the search for alternative harvest sites. The reamer-irrigation-aspirator (RIA) provides continuous irrigation and suction during reaming of long bones. The aspirated contents pass via a filter, trapping bony fragments, before moving into a ‘waste’ bag from which MSCs have been previously isolated. We examined the liquid and solid phases, performed a novel digestion of the solid phase, and made a comparative assessment in terms of number, phenotype and differentiation capacity with matched ICBMA. The solid fraction from the filtrate was digested for 60 minutes at 37°C with collagenase. Enumeration was performed via the colony-forming unit fibroblast (CFU-F) assay. Passage (P2) cells were differentiated towards osteogenic, adipogenic and chondrogenic lineages, and their phenotypes assessed using flow cytometry (CD33, CD34, CD45, CD73, CD90, and CD105). MSCs from the RIA phases were able to differentiate at least as well as those from ICBMA, and all fractions had phenotypes consistent with other established sources. The median number of colonies for the three groups was: ICBMA = 8.5 (2 to 86), RIA-liquid = 19.5 (4 to 90), RIA-solid = 109 (67 to 200) per 200 μl. The mean total yield of cells for the three groups was: ICBMA = 920 (0 to 4275), RIA-liquid = 114 983 (16 500 to 477 750), RIA-solid = 12 785 (7210 to 28 475). The RIA filtrate contains large numbers of MSCs that could potentially be extracted without enzymatic digestion and used for bone repair without prior cell expansion.