Our aim in this prospective study was to evaluate the outcome of total shoulder replacement in the treatment of young and middle-aged active patients with primary glenohumeral osteoarthritis. We reviewed 21 patients (21 shoulders) with a mean age of 55 years (37 to 60). The mean follow-up was seven years (5 to 9). The same anatomical, third-generation, cemented implant had been used in all patients. All the patients were evaluated radiologically and clinically using the Constant and Murley score. No patients required revision. In one a tear of the supraspinatus tendon occurred. Overall, 20 patients (95%) were either very satisfied (n = 18) or satisfied (n = 2) with the outcome. Significant differences (p <
0.0001) were found for all categories of the Constant and Murley score pre- and post-operatively. The mean Constant and Murley score increased from 24.1 points (10 to 45) to 64.5 points (39 to 93), and the relative score from 30.4% (11% to 50%) to 83% (54% to 116%). No clinical or radiological signs of loosening of the implant were seen. For young and middle-aged patients with osteoarthritis, third-generation total shoulder replacement is a viable method of treatment with a low rate of complications and excellent results in the mid-term.
In skeletally immature patients, resection of
bone tumours and reconstruction of the lower limb often results
in leg-length discrepancy. The Stanmore non-invasive extendible
endoprosthesis, which uses electromagnetic induction, allows post-operative
lengthening without anaesthesia. Between 2002 and 2009, 55 children
with a mean age of 11.4 years (5 to 16) underwent reconstruction
with this prosthesis; ten patients (18.2%) died of disseminated
disease and one child underwent amputation due to infection. We
reviewed 44 patients after a mean follow-up of 41.2 months (22 to
104). The mean Musculoskeletal Tumor Society score was 24.7 (8 to
30) and the Toronto Extremity Salvage score was 92.3% (55.2% to
99.0%). There was no local recurrence of tumour. Complications developed
in 16 patients (29.1%) and ten (18.2%) underwent revision. The mean length gained per patient was 38.6 mm (3.5 to 161.5),
requiring a mean of 11.3 extensions (1 to 40), and ten component
exchanges were performed in nine patients (16.4%) after attaining
the maximum lengthening capacity of the implant. There were 11 patients
(20%) who were skeletally mature at follow-up, ten of whom had equal
leg lengths and nine had a full range of movement of the hip and
knee. This is the largest reported series using non-invasive extendible
endoprostheses after excision of primary bone tumours in skeletally
immature patients. The technique produces a good functional outcome,
with prevention of limb-length discrepancy at skeletal maturity.
Pain is the main indication for performing total knee replacement (TKR). In most patients after TKR there is an improvement, but a few continue to have pain. Generally, the cause of the pain can be addressed when it is identified. However, unexplained pain can be more difficult to manage because revision surgery is likely to be unrewarding in this group. In our study of 622 cemented TKRs in 512 patients with a mean age of 69 years (23 to 90) treated between January 1995 and August 1998, we identified 24 patients (knees) with unexplained pain at six months. This group was followed for five years (data was unavailable for 18 knees) and ten patients (55.5%) went on to show an improvement without intervention. In the case of unexplained pain, management decisions must be carefully considered, but reassurance can be offered to patients that the pain will improve in more than half with time.
The biological significance of cobalt-chromium wear particles from metal-on-metal hip replacements may be different to the effects of the constituent metal ions in solution. Bacteria may be able to discriminate between particulate and ionic forms of these metals because of a transmembrane nickel/cobalt-permease. It is not known whether wear particles are bacteriocidal. We compared the doubling time of coagulase negative staphylococcus, Doubling time halved in metal-on-metal (p = 0.003) and metal-on-polyethylene (p = 0.131) particulate debris compared with the control. Bacterial nickel/cobalt-transporters allow metal ions but not wear particles to cross bacterial membranes. This may be useful for testing the biological characteristics of different wear debris. This experiment also shows that metal-on-metal hip wear debris is not bacteriocidal.
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.
The outcomes of 261 nerve injuries in 100 patients
were graded good in 173 cases (66%), fair in 70 (26.8%) and poor in
18 (6.9%) at the final review (median 28.4 months (1.3 to 64.2)).
The initial grades for the 42 sutures and graft were 11 good, 14
fair and 17 poor. After subsequent revision repairs in seven, neurolyses
in 11 and free vascularised fasciocutaneous flaps in 11, the final
grades were 15 good, 18 fair and nine poor. Pain was relieved in
30 of 36 patients by nerve repair, revision of repair or neurolysis,
and flaps when indicated. The difference in outcome between penetrating
missile wounds and those caused by explosions was not statistically
significant; in the latter group the onset of recovery from focal
conduction block was delayed (mean 4.7 months (2.5 to 10.2)
Evaluation of patients with painful total knee replacement requires a thorough clinical examination and relevant investigations in order to reach a diagnosis. Awareness of the common and uncommon problems leading to painful total knee replacement is useful in the diagnostic approach. This review article aims to act as a guide to the evaluation of patients with painful total knee replacement.
We compared the alignment of 39 total knee replacements implanted using the conventional alignment guide system with 37 implanted using a CT-based navigation system, performed by a single surgeon. The knees were evaluated using full-length weight-bearing anteroposterior radiographs, lateral radiographs and CT scans. The mean hip-knee-ankle angle, coronal femoral component angle and coronal tibial component angle were 181.8° (174.2° to 188.3°), 88.5° (84.0° to 91.8°) and 89.7° (86.3° to 95.1°), respectively for the conventional group and 180.8° (178.2° to 185.1°), 89.3° (85.8° to 92.0°) and 89.9° (88.0° to 93.0°), respectively for the navigated group. The mean sagittal femoral component angle was 85.5° (80.6° to 92.8°) for the conventional group and 89.6° (85.5° to 94.0°) for the navigated group. The mean rotational femoral and tibial component angles were −0.7° (−8.8° to 9.8°) and −3.3° (−16.8° to 5.8°) for the conventional group and −0.6° (−3.5° to 3.0°) and 0.3° (−5.3° to 7.7°) for the navigated group. The ideal angles of all alignments in the navigated group were obtained at significantly higher rates than in the conventional group. Our results demonstrated significant improvements in component positioning with a CT-based navigation system, especially with respect to rotational alignment.
We suggest that different mechanisms underlie joint pain at rest and on movement in osteoarthritis and that separate assessment of these two features with a visual analogue scale (VAS) offers better information about the likely effect of a total knee replacement (TKR) on pain. The risk of persistent pain after TKR may relate to the degree of central sensitisation before surgery, which might be assessed by determining the pain threshold to an electrical stimulus created by a special tool, the Pain Matcher. Assessments were performed in 69 patients scheduled for TKR. At 18 months after operation, separate assessment of pain at rest and with movement was again carried out using a VAS in order to enable comparison of pre- and post-operative measurements. A less favourable outcome in terms of pain relief was observed for patients with a high pre-operative VAS score for pain at rest and a low pain threshold, both features which may reflect a central sensitisation mechanism.
Given the growing prevalence of obesity around
the world and its association with osteoarthritis of the knee, orthopaedic
surgeons need to be familiar with the management of the obese patient
with degenerative knee pain. The precise mechanism by which obesity
leads to osteoarthritis remains unknown, but is likely to be due
to a combination of mechanical, humoral and genetic factors. Weight loss has clear medical benefits for the obese patient
and seems to be a logical way of relieving joint pain associated
with degenerative arthritis. There are a variety of ways in which
this may be done including diet and exercise, and treatment with
drugs and bariatric surgery. Whether substantial weight loss can
delay or even reverse the symptoms associated with osteoarthritis
remains to be seen. Surgery for osteoarthritis in the obese patient can be technically
more challenging and carries a risk of additional complications.
Substantial weight loss before undertaking total knee replacement
is advisable. More prospective studies that evaluate the effect
of significant weight loss on the evolution of symptomatic osteoarthritis
of the knee are needed so that orthopaedic surgeons can treat this
patient group appropriately.
This study compared the outcome of total knee
replacement (TKR) in adult patients with fixed- and mobile-bearing prostheses
during the first post-operative year and at five years’ follow-up,
using gait parameters as a new objective measure. This double-blind
randomised controlled clinical trial included 55 patients with mobile-bearing (n
= 26) and fixed-bearing (n = 29) prostheses of the same design,
evaluated pre-operatively and post-operatively at six weeks, three
months, six months, one year and five years. Each participant undertook
two walking trials of 30 m and completed the EuroQol questionnaire,
Western Ontario and McMaster Universities osteoarthritis index,
Knee Society score, and visual analogue scales for pain and stiffness.
Gait analysis was performed using five miniature angular rate sensors
mounted on the trunk (sacrum), each thigh and calf. The study population
was divided into two groups according to age (≤ 70 years Improvements in most gait parameters at five years’ follow-up
were greater for fixed-bearing TKRs in older patients (>
70 years),
and greater for mobile-bearing TKRs in younger patients (≤ 70 years).
These findings should be confirmed by an extended age controlled
study, as the ideal choice of prosthesis might depend on the age
of the patient at the time of surgery.
We previously compared the component alignment in total knee replacement using a computer-navigated technique with a conventional jig-based method. We randomly allocated 71 patients to undergo either computer-navigated or conventional replacement. An improved alignment was seen in the computer-navigated group. The patients were then followed up post-operatively for two years, using the Knee Society score, the Short Form-36 health survey, the Western Ontario and McMaster Universities osteoarthritis index, the Bartlett Patellar pain questionnaire and the Oxford knee score, to assess functional outcome. At two years post-operatively 60 patients were available for assessment, 30 in each group and 62 patients completed a postal survey. No patient in either group had undergone revision. All variables were analysed for differences between the groups either by Student’s The clinical outcome of the patients with a computer-navigated knee replacement appears to be no different to that of a more conventional jig-based technique at two years post-operatively, despite the better alignment achieved with computer-navigated surgery.
The purpose of this prospective, randomised study
was to evaluate the clinical and radiological results comparing the
identical cemented or cementless NexGen total knee prostheses implanted
bilaterally in the same patient. Sequential simultaneous bilateral
total knee replacements were performed in 50 patients (100 knees).
There were 39 women and 11 men with a mean age of 58.4 years (51
to 67) who received a cemented prosthesis in one knee and a cementless
prosthesis in the other. The mean follow-up was 13.6 years (13 to
14). At final review, the mean Knee Society scores (96.2 (82 to
100)
We prospectively assessed the benefits of using either a range-of-movement technique or an anatomical landmark method to determine the rotational alignment of the tibial component during total knee replacement. We analysed the cut proximal tibia intraoperatively, determining anteroposterior axes by the range-of-movement technique and comparing them with the anatomical anteroposterior axis. We found that the range-of-movement technique tended to leave the tibial component more internally rotated than when anatomical landmarks were used. In addition, it gave widely variable results (mean 7.5°; 2° to 17°), determined to some extent by which posterior reference point was used. Because of the wide variability and the possibilities for error, we consider that it is inappropriate to use the range-of-movement technique as the sole method of determining alignment of the tibial component during total knee replacement.
This conversation represents an attempt by several
arthroplasty surgeons to critique several abstracts presented over
the last year as well as to use them as a jumping off point for trying
to figure out where they fit in into our current understanding of
multiple issues in modern hip and knee arthroplasty.
Between April 1999 and April 2004, 3497 Birmingham hips were inserted by 89 surgeons. Fracture of the neck of the femur occurred in 50 patients, an incidence of 1.46%. Complete data were available for 45 patients in whom the incidence was 1.91% for women and 0.98% for men. The relative risk of fracture for women The mean time to fracture was 15.4 weeks. In women the fractures occurred at a mean of 18.5 weeks and were more likely to have been preceded by a pro-dromal phase of pain and limping. In men the mean time to fracture was 13.5 weeks. Significant varus placement of the femoral component, intra-operative notching of the femoral neck and technical problems were common factors in 85% of cases.
Correct positioning and alignment of components during primary total knee replacement (TKR) is widely accepted to be an important predictor of patient satisfaction and implant durability. This retrospective study reports the effect of the post-operative mechanical axis of the lower limb in the coronal plane on implant survival following primary TKR. A total of 501 TKRs in 396 patients were divided into an aligned group with a neutral mechanical axis (± 3°) and a malaligned group where the mechanical axis deviated from neutral by >
3°. At 15 years’ follow-up, 33 of 458 (7.2%) TKRs were revised for aseptic loosening. Kaplan-Meier survival analysis showed a weak tendency towards improved survival with restoration of a neutral mechanical axis, but this did not reach statistical significance (p = 0.47). We found that the relationship between survival of a primary TKR and mechanical axis alignment is weaker than that described in a number of previous reports.
We compared the results of 146 patients who received an anatomic modular knee fixed-bearing total knee replacement (TKR) in one knee and a low contact stress rotating platform mobile-bearing TKR in the other. There were 138 women and eight men with a mean age of 69.8 years (42 to 80). The mean follow-up was 13.2 years (11.0 to 14.5). The patients were assessed clinically and radiologically using the rating systems of the Hospital for Special Surgery and the Knee Society at three months, six months, one year, and annually thereafter. The assessment scores of both rating systems pre-operatively and at the final review did not show any statistically significant differences between the two designs of implant. In the anatomic modular knee group, one knee was revised because of aseptic loosening of the tibial component and one because of infection. In addition, three knees were revised because of wear of the polyethylene tibial bearing. In the low contact stress group, two knees were revised because of instability requiring exchange of the polyethylene insert and one because of infection. The radiological analysis found no statistical difference in the incidence of radiolucent lines at the final review (Student’s We found no evidence of the superiority of one design over the other at long-term follow-up.