The requirement for release of collateral ligaments to achieve a stable, balanced total knee replacement has been reported to arise in about 50% to 100% of procedures. This wide range reflects a lack of standardised quantitative indicators to determine the necessity for a release. Using recent advances in computerised navigation, we describe two navigational predictors which provide quantitative measures that can be used to identify the need for release. The first was the ability to restore the mechanical axis before any bone resection was performed and the second was the discrepancy in the measured medial and lateral joint spaces after the tibial osteotomy, but before any femoral resection. These predictors showed a significant association with the need for collateral ligament release (p <
0.001). The first predictor using the knee stress test in extension showed a sensitivity of 100% and a specificity of 98% and the second, the difference between medial and lateral gaps in millimetres, a sensitivity of 83% and a specificity of 95%. The use of the two navigational predictors meant that only ten of the 93 patients required collateral ligament release to achieve a stable, neutral knee.
In 100 patients the fulcrum axis which is the line connecting the anterior tip of the coracoid and the posterolateral angle of the acromion, was used to position true anteroposterior radiographs of the shoulder. This method was then compared with the conventional radiological technique in a further 100 patients. Three orthopaedic surgeons counted the number of images without overlap between the humeral head and glenoid and calculated the amount of the glenoid surface visible in each radiograph. The analysis was repeated for intraobserver reliability. The learning curves of both techniques were studied. The amount of free visible glenoid space was significantly higher using the fulcrum-axis method (64 vs 31) and the comparable glenoid size increased significantly (8.56 vs 6.47). Thus the accuracy of the anteroposterior radiographs of the shoulder is impaired by using this technique. The intra and interobserver reliability showed a high consistency. No learning curve was observed for either technique.
We attempted to characterise the biological quality
and regenerative potential of chondrocytes in osteochondritis dissecans
(OCD). Dissected fragments from ten patients with OCD of the knee
(mean age 27.8 years (16 to 49)) were harvested at arthroscopy.
A sample of cartilage from the intercondylar notch was taken from
the same joint and from the notch of ten patients with a traumatic
cartilage defect (mean age 31.6 years (19 to 52)). Chondrocytes
were extracted and subsequently cultured. Collagen types 1, 2, and
10 mRNA were quantified by polymerase chain reaction. Compared with
the notch chondrocytes, cells from the dissecate expressed similar
levels of collagen types 1 and 2 mRNA. The level of collagen type
10 message was 50 times lower after cell culture, indicating a loss
of hypertrophic cells or genes. The high viability, retained capacity
to differentiate and metabolic activity of the extracted cells suggests
preservation of the intrinsic repair capability of these dissecates.
Molecular analysis indicated a phenotypic modulation of the expanded
dissecate chondrocytes towards a normal phenotype. Our findings
suggest that cartilage taken from the dissecate can be reasonably
used as a cell source for chondrocyte implantation procedures.
We report the effectiveness of revision of total
elbow replacement by re-cementing. Between 1982 and 2004, 53 elbows
in 52 patients were treated with re-cementing of a total elbow replacement
into part or all of the existing cement mantle or into the debrided
host-bone interface, without the use of structural bone augmentation
or a custom prosthesis. The original implant revision was still
The management of nonunion following high tibial osteotomy by total knee replacement (TKR) has been reported previously. We have extended the treatment to embrace cases with an infected high tibial osteotomy by performing an initial debridement with a period of antibiotic treatment followed by TKR. We have reviewed the results of seven knees in six patients with a mean follow-up of 40.5 months (20 to 57) after the staged TKR. At the latest follow-up, all the pseudarthroses had healed and there had been no recurrence of infection. The mean Hospital for Special Surgery knee score improved from 51.2 (35 to 73) to a mean of 91.7 (84 to 98) at final review. Management of nonunion following high tibial osteotomy with a TKR can be extended to infected cases when treated in two stages with a debridement and antibiotic therapy prior to TKR.
We report the clinical and radiological results of a two- to three-year prospective randomised study which was designed to compare a minimally-invasive technique with a standard technique in total knee replacement and was undertaken between January 2004 and May 2007. The mini-midvastus approach was used on 50 patients (group A) and a standard approach on 50 patients (group B). The mean follow-up in both groups was 23 months (24 to 35). The functional outcome was better in group A up to nine months after operation, as shown by statistically significant differences in the mean function score, mean total score and the mean Oxford knee score (all, p = 0.05). Patients in group A had statistically significant greater early flexion (p = 0.04) and reached their greatest mean knee flexion of 126.5° (95° to 135°) 21 days after operation. However, at final follow-up there was no significant difference in the mean maximum flexion between the groups (p = 0.08). Technical errors were identified in six patients from group A (12%) on radiological evaluation. Based on these results, the authors currently use minimally-invasive techniques in total knee replacement in selected cases only.
We performed a retrospective examination of the
anteroposterior pelvic CT scout views of 419 randomly selected patients between
April 2004 and August 2009 in order to determine the prevalence
of cam-type femoroacetabular deformity in the asymptomatic population.
The CT scans had all been undertaken for conditions unrelated to
disorders of the hip. The frequency of cam-type femoroacetabular
deformity was assessed by measuring the α-angle of each hip on the
anteroposterior images. The α-angles were classified according to
the Copenhagen Osteoarthritis Study. Among 215 male hips (108 patients)
the mean α-angle was 59.12° (37.75° to 103.50°). Of these, a total
of 30 hips (13.95%) were defined as pathological, 32 (14.88%) as
borderline and 153 (71.16%) as normal. Among 540 female hips (272
patients) the mean α-angle was 45.47° (34.75° to 87.00°), with 30
hips (5.56%) defined as pathological, 33 (6.11%) as borderline and
477 (88.33%) as normal. It appears that the cam-type femoroacetabular
deformity is not rare among the asymptomatic population. These anatomical
abnormalities, as determined by an increased α-angle, appear to
be twice as frequent in men as in women. Although an association
between osteoarthritis and femoroacetabular impingement is believed
to exist, a long-term epidemiological study is needed to determine
the natural history of these anatomical abnormalities.
The results of further soft-tissue release of 79 feet in 60 children with recurrent idiopathic congenital talipes equinovarus were evaluated. The mean age of the children at the time of re-operation was 5.8 years (15 months to 14.5 years). Soft-tissue release was performed in all 79 feet and combined with distal calcaneal excision in 52 feet. The mean follow-up was 12 years (4 to 32). At the latest follow-up the result was excellent or good in 61 feet (77%) according to the Ghanem and Seringe scoring system. The results was considered as fair in 14 feet (18%), all of whom had functional problems and eight had anatomical abnormalities. Four feet (5%) were graded as poor on both functional and anatomical grounds. The results were independent of the age at which revision was undertaken.
We carried out a prospective, continuous study on 529 patients who underwent primary total knee replacement between January 2006 and December 2007 at a major teaching hospital. The aim was to investigate weight change and the functional and clinical outcome in non-obese and obese groups at 12 months post-operatively. The patients were grouped according to their pre-operative body mass index (BMI) as follows: non-obese (BMI <
30 kg/m2), obese (BMI At 12 months, a clinically significant weight loss of ≥ 5% had occurred in 40 (12.6%) of the obese patients, but 107 (21%) gained weight. The change in the International Knee Society score was less in obese and morbidly obese compared with non-obese patients (p = 0.016). Adverse events occurred in 30 (14.2%) of the non-obese, 59 (22.6%) of the obese and 20 (35.1%) of the morbidly obese patients (p = 0.001).
In light of the growing number of elderly osteopenic
patients with distal humeral fractures, we discuss the history of
their management and current trends. Under most circumstances operative
fixation and early mobilisation is the treatment of choice, as it
gives the best results. The relative indications for and results
of total elbow replacement
We retrospectively analysed the clinical results of 30 patients with injuries of the sternoclavicular joint at a minimum of 12 months’ follow-up. A closed reduction was attempted in 14 cases. It was successful in only five of ten dislocations, and failed in all four epiphyseal disruptions. A total of 25 patients underwent surgical reduction, in 18 cases in conjunction with a stabilisation procedure. At a mean follow-up of 60 months, four patients were lost to follow-up. The functional results in the remainder were satisfactory, and 18 patients were able to resume their usual sports activity at the same level. There was no statistically significant difference between epiphyseal disruption and sternoclavicular dislocation (p >
0.05), but the functional scores (Simple Shoulder Test, Disability of Arm, Shoulder, Hand, and Constant scores) were better when an associated stabilisation procedure had been performed rather than reduction alone (p = 0.05, p = 0.04 and p = 0.07, respectively). We recommend meticulous pre-operative clinical assessment with CT scans. In sternoclavicular dislocation managed within the first 48 hours and with no sign of mediastinal complication, a closed reduction can be attempted, although this was unsuccessful in half of our cases. A control CT scan is mandatory. In all other cases, and particularly if epiphyseal disruption is suspected, we recommend open reduction with a stabilisation procedure by costaclavicular cerclage or tenodesis. The use of a Kirschner wire should be avoided.
Studies describing the effect of body mass index (BMI) on the outcome of total hip replacement have been inconclusive and contradictory. We examined the effect of BMI on medium-term outcome in a cohort of 1617 patients who underwent a primary total hip replacement for osteoarthritis. These patients were followed prospectively for five years with the outcomes of dislocation, revision, duration of surgery and deep and superficial infection studied, as well as collecting Harris hip scores (HHS) and Short-Form 36 (SF-36) questionnaires pre-operatively and at review. A multivariate analysis was performed to see whether BMI is an independent predictor of poor outcome. We found that patients with a BMI of ? 35 kg/m2 have a 4.42 times higher rate of dislocation than those with a BMI <
25 kg/m2. Increasing BMI is also associated with superficial infection and poorer HHS and SF-36 scores at five years. These trends remain significant even when multivariate analysis adjusts for age, gender, prosthesis, operating consultant, pre-operative HHS and SF-36, and comorbidities including diabetes mellitus, cardiac disease and osteoporosis. Despite the increased risks, the five-year outcome scores indicate that obese patients have much to gain from total hip replacement. Thus total hip replacement should not be withheld from patients solely on the grounds of an elevated BMI. However, longer-term follow-up of this cohort is required to establish whether adverse outcomes become more evident with time.
In 2004 we described the ten-year prospective results of 38 total hip replacements using the Furlong hydroxyapatite-ceramic-coated femoral component in 35 patients <
50 years old. We have now reviewed the surviving 35 arthroplasties in 33 patients at a mean of 16 years (10.3 to 19.9). The mean age of the surviving patients at the time of operation was 41.3 years (26.0 to 49.0). Of these, eight have undergone revision of their acetabular component for aseptic loosening. None of the femoral components has had revision for aseptic loosening giving a survival rate of 100% at 16 years (95% confidence interval 89% to 100%). The Furlong hydroxyapatite-ceramic-coated femoral component gives excellent long-term survival in young and active patients.
Metal-on-metal hip resurfacing is commonly performed for osteoarthritis in young active patients. We have observed cystic or solid masses, which we have called inflammatory pseudotumours, arising around these devices. They may cause soft-tissue destruction with severe symptoms and a poor outcome after revision surgery. The aim of this study was to determine the incidence of and risk factors for pseudotumours that are serious enough to require revision surgery. Since 1999, 1419 metal-on-metal hip resurfacings have been implanted by our group in 1224 patients; 1.8% of the patients had a revision for pseudotumour. In this series the Kaplan-Meier cumulative revision rate for pseudotumour increased progressively with time. At eight years, in all patients, it was 4% (95% confidence interval (CI) 2.2 to 5.8). Factors significantly associated with an increase in revision rate were female gender (p <
0.001), age under 40 (p = 0.003), small components (p = 0.003), and dysplasia (p = 0.019), whereas implant type was not (p = 0.156). These factors were inter-related, however, and on fitting a Cox proportional hazard model only gender (p = 0.002) and age (p = 0.024) had a significant independent influence on revision rate; size nearly reached significance (p = 0.08). Subdividing the cohort according to significant factors, we found that the revision rate for pseudotumours in men was 0.5% (95% CI 0 to 1.1) at eight years wheras in women over 40 years old it was 6% (95% CI 2.3 to 10.1) at eight years and in women under 40 years it was 13.1% at six years (95% CI 0 to 27) (p <
0.001). We recommend that resurfacings are undertaken with caution in women, particularly those under 40 years of age but they remain a good option in young men. Further work is required to understand the aetiology of pseudotumours so that this complication can be avoided.
We evaluated the safety and efficacy of total
knee replacement in patients receiving continuous warfarin therapy. We identified 24 consecutive patients receiving long-term warfarin
therapy who underwent total knee replacement between 2006 and 2008
and compared them with a group of age- and gender-matched patients
not on long-term anticoagulation. Primary observations were changes
in haemoglobin, transfusion rates and complications. Secondary observations
were fluctuations in the international normalised ratio (INR) and
post-operative range of movement. There was no significant difference between the two groups in
pre- or post-operative haemoglobin, incidence of transfusion or
incidence of post-operative complications. There were no surgical
delays due to a high INR level. The mean change in INR during the
peri-operative phase was minimal (mean 0.4; Current American College of Chest Physicians guidelines recommend
bridging therapy for high-risk patients receiving oral anticoagulation
and undergoing major orthopaedic procedures. We have shown that
a safe alternative is to continue the steady-state warfarin peri-operatively
in patients on long-term anticoagulation requiring total knee replacement.
For over a decade, bisphosphonate administration
has evolved and become the cornerstone of the prevention and treatment
of fragility fractures. Millions of post-menopausal women have relied
on, and continue to depend on, the long-acting, bone density-maintaining
pharmaceutical drug to prevent low-energy fractures. In return,
we have seen the number of fragility fractures decrease, along with
associated costs and emotional benefits. However, with any drug,
there are often concerns with side effects and complications, and
this unique drug class is seeing one such complication in atypical
subtrochanteric femoral fracture, counterproductive to that which
it was designed to prevent. This has created concern over long-term
bisphosphonate administration and its potential link to these atypical
fractures. There is controversial evidence surrounding such a definitive
link, and no protocol for managing these fractures. This review offers the latest information regarding this rare
but increasingly controversial adverse effect and its potential
connection to one of the most successful forms of treatment that
is available for the management of fragility fractures.
We undertook a randomised controlled trial to
compare the piriformis-sparing approach with the standard posterior approach
used for total hip replacement (THR). We recruited 100 patients
awaiting THR and randomly allocated them to either the piriformis-sparing
approach or the standard posterior approach. Pre- and post-operative
care programmes and rehabilitation regimes were identical for both
groups. Observers were blinded to the allocation throughout; patients
were blinded until the two-week assessment. Follow-up was at six
weeks, three months, one year and two years. In all 11 patients
died or were lost to follow-up. There was no significant difference between groups for any of
the functional outcomes. However, for patients in the piriformis-sparing
group there was a trend towards a better six-minute walk test at
two weeks and greater patient satisfaction at six weeks. The acetabular
components were less anteverted (p = 0.005) and had a lower mean
inclination angle (p = 0.02) in the piriformis-sparing group. However,
in both groups the mean component positions were within Lewinnek’s
safe zone. Surgeons perceived the piriformis-sparing approach to
be significantly more difficult than the standard approach (p =
0.03), particularly in obese patients. In conclusion, performing THR through a shorter incision involving
sparing piriformis is more difficult and only provides short-term
benefits compared with the standard posterior approach.
Between January 1984 and January 1986, 131 porous-coated anatomic total hip replacements were performed in 119 consecutive patients. Of these, 100 patients (110 hips) who were alive at a minimum of 18 years after replacement were included in the study. The mean age of the patients at surgery was 48.4 years and that of surviving patients at the latest follow-up was 67.8 years. The mean duration of the clinical and radiological follow-up was 19.4 years (18 to 20). The mean Harris hip score initially improved from 55 points before to 95 points at two years after operation, but subsequently decreased to 91 points after six years, 87 points after 11.2 years, and 85 points after 19.4 years. At the final follow-up, 23 hips (18%) of the entire cohort and 21% of survivors had undergone revision because of loosening or osteolysis of the acetabular component and eight hips (6%) of the entire cohort and 7% of survivors for loosening or osteolysis of the femoral component. Only four femoral components (4%) were revised for isolated aseptic loosening without osteolysis and two (2%) for recurrent dislocation. On the basis of these long-term results, the porous-coated anatomic femoral component survived for a minimum of 18 years after operation while the acetabular component was less durable. The findings identify the principles of uncemented joint replacement which can be applied to current practice.