The interest in unicompartmental knee arthroplasty (UKA) for
medial osteoarthritis has increased rapidly but the long-term follow-up
of the Oxford UKAs has yet to be analysed in non-designer centres.
We have examined our ten- to 15-year clinical and radiological follow-up
data for the Oxford Phase III UKAs. Between January 1999 and January 2005 a total of 138 consecutive
Oxford Phase III arthroplasties were performed by a single surgeon
in 129 patients for medial compartment osteoarthritis (71 right
and 67 left knees, mean age 72.0 years (47 to 91), mean body mass
index 28.2 (20.7 to 52.2)). Both clinical data and radiographs were
prospectively recorded and obtained at intervals. Of the 129 patients,
32 patients (32 knees) died, ten patients (12 knees) were not able
to take part in the final clinical and radiological assessment due
to physical and mental conditions, but via telephone interview it
was confirmed that none of these ten patients (12 knees) had a revision
of the knee arthroplasty. One patient (two knees) was lost to follow-up.Aims
Patients and Methods
T-cells are considered to play an important role in the inflammatory response causing arthroplasty failure. The study objectives were to investigate the composition and distribution of CD4+ T-cell phenotypes in the peripheral blood (PB) and synovial fluid (SF) of patients undergoing revision surgery for failed metal-on-metal (MoM) and metal-on-polyethylene (MoP) hip arthroplasties, and in patients awaiting total hip arthroplasty. In this prospective case-control study, PB and SF were obtained from 22 patients (23 hips) undergoing revision of MoM (n = 14) and MoP (n = 9) hip arthroplasties, with eight controls provided from primary hip osteoarthritis cases awaiting arthroplasty. Lymphocyte subtypes in samples were analysed using flow cytometry.Objectives
Methods
This review examines the future of total hip arthroplasty, aiming to avoid past mistakes
As adverse events related to metal on metal hip
arthroplasty have been better understood, there has been increased
interest in toxicity related to the high circulating levels of cobalt ions.
However, distinguishing true toxicity from benign elevations in
cobalt levels can be challenging. The purpose of this review is
to examine the use of cobalt alloys in total hip arthroplasty, to
review the methods of measuring circulating cobalt levels, to define
a level of cobalt which is considered pathological and to review
the pathophysiology, risk factors and treatment of cobalt toxicity.
To the best of our knowledge, there are 18 published cases where
cobalt metal ion toxicity has been attributed to the use of cobalt-chromium
alloys in hip arthroplasty. Of these cases, the great majority reported
systemic toxic reactions at serum cobalt levels more than 100 μg/L.
This review highlights some of the clinical features of cobalt toxicity,
with the goal that early awareness may decrease the risk factors
for the development of cobalt toxicity and/or reduce its severity. Take home message: Severe adverse events can arise from the release
of cobalt from metal-on-metal arthroplasties, and as such, orthopaedic
surgeons should not only be aware of the presenting problems, but
also have the knowledge to treat appropriately. Cite this article:
This randomised trial evaluated the outcome of
a single design of unicompartmental arthroplasty of the knee (UKA) with
either a cemented all-polyethylene or a metal-backed modular tibial
component. A total of 63 knees in 45 patients (17 male, 28 female)
were included, 27 in the all-polyethylene group and 36 in the metal-backed
group. The mean age was 57.9 years (39.6 to 76.9). At a mean follow-up
of 6.4 years (5 to 9.9), 11 all-polyethylene components (41%) were
revised (at a mean of 5.8 years; 1.4 to 8.0) post-operatively and
two metal-backed components were revised (at one and five years).
One revision in both groups was for unexplained pain, one in the
metal-backed group was for progression of osteoarthritis. The others
in the all-polyethylene group were for aseptic loosening. The survivorship
at seven years calculated by the Kaplan–Meier method for the all-polyethylene
group was 56.5% (95% CI 31.9 to 75.2, number at risk 7) and for
the metal-backed group was 93.8% (95% CI 77.3 to 98.4, number at
risk 16) This difference was statistically significant (p <
0.001).
At the most recent follow-up, significantly better mean Western
Ontario and McMaster Universities Arthritis Index Scores were found
in the all-polyethylene group (13.4 This randomised study demonstrates that all-polyethylene components
in this design of fixed bearing UKA had unsatisfactory results with
significantly higher rates of failure before ten years compared
with the metal-back components. Cite this article:
We aimed to assess the comparability of data in joint replacement
registries and identify ways of improving the comparisons between
registries and the overall monitoring of joint replacement surgery. We conducted a review of registries that are full members of
the International Society of Arthroplasty Registries with publicly
available annual reports in English. Of the six registries which
were included, we compared the reporting of: mean age, definitions
for revision and re-operation, reasons for revision, the approach
to analysing revisions, and patient-reported outcome measures (PROMs)
for primary and revision total hip arthroplasty (THA) and hip resurfacing
arthroplasty (HRA).Aims
Materials and Methods
Surface hip replacement (SHR) is generally used
in younger, active patients as an alternative conventional total
hip replacement in part because of the ability to preserve femoral
bone. This major benefit of surface replacement will only hold true
if revision procedures of SHRs are found to provide good clinical
results. A retrospective review of SHR revisions between 2007 and 2012
was presented, and the type of revision and aetiologies were recorded.
There were 55 SHR revisions, of which 27 were in women. At a mean
follow-up of 2.3 years (0.72 to 6.4), the mean post-operative Harris
hip score (HHS) was 94.8 (66 to 100). Overall 23 were revised for mechanical
reasons, nine for impingement, 13 for metallosis, nine for unexplained
pain and one for sepsis. Of the type of revision surgery performed,
14 were femoral-only revisions; four were acetabular-only revisions,
and 37 were complete revisions. We did not find that clinical scores were significantly different
between gender or different types of revisions. However, the mean
post-operative HHS was significantly lower in patients revised for
unexplained pain compared with patients revised for mechanical reasons
(86.9 (66 to 100) Based on the overall clinical results, we believe that revision
of SHR can have good or excellent results and warrants a continued
use of the procedure in selected patients. Close monitoring of these
patients facilitates early intervention, as we believe that tissue
damage may be related to the duration of an ongoing problem. There
should be a low threshold to revise a surface replacement if there
is component malposition, rising metal ion levels, or evidence of
soft-tissue abnormalities. Cite this article:
Pre-operative planning for total hip replacement
(THR) is challenging in hips with severe acetabular deformities, including
those with a hypoplastic acetabulum or severe defects and in the
presence of arthrodesis or ankylosis. We evaluated whether a Rapid
Prototype (RP) model, which is a life-sized reproduction based on
three-dimensional CT scans, can determine the feasibility of THR
and provide information about the size and position of the acetabular component
in severe acetabular deformities. THR was planned using an RP model
in 21 complex hips in five men (five hips) and 16 women (16 hips)
with a mean age of 47.7 years (24 to 70) at operation. An acetabular
component was implanted successfully and THR completed in all hips.
The acetabular component used was within 2 mm of the predicted size
in 17 hips (80.9%). All of the acetabular components and femoral
stems had radiological evidence of bone ingrowth and stability at
the final follow-up, without any detectable wear or peri-prosthetic
osteolysis. The RP model allowed a simulated procedure pre-operatively
and was helpful in determining the feasibility of THR pre-operatively,
and to decide on implant type, size and position in complex THRs. Cite this article:
The December 2014 Hip &
Pelvis Roundup360 looks at: Sports and total hips; topical tranexamic acid and blood conservation in hip replacement; blind spots and biases in hip research; no recurrence in cam lesions at two years; to drain or not to drain?; sonication and diagnosis of implant associated infection; and biomarkers and periprosthetic infection
Previous studies of failure mechanisms leading
to revision total knee replacement (TKR) performed between 1986 and
2000 determined that many failed early, with a disproportionate
amount accounted for by infection and implant-associated factors
including wear, loosening and instability. Since then, efforts have
been made to improve implant performance and instruct surgeons in
best practice. Recently our centre participated in a multi-centre evaluation
of 844 revision TKRs from 2010 to 2011. The purpose was to report
a detailed analysis of failure mechanisms over time and to see if
failure modes have changed over the past 10 to 15 years. Aseptic
loosening was the predominant mechanism of failure (31.2%), followed
by instability (18.7%), infection (16.2%), polyethylene wear (10.0%),
arthrofibrosis (6.9%) and malalignment (6.6%). The mean time to
failure was 5.9 years (ten days to 31 years), 35.3% of all revisions
occurred at less than two years, and 60.2% in the first five years.
With improvements in implant and polyethylene manufacture, polyethylene
wear is no longer a leading cause of failure. Early mechanisms of
failure are primarily technical errors. In addition to improving
implant longevity, industry and surgeons must work together to decrease
these technical errors. All reports on failure of TKR contain patients
with unexplained pain who not infrequently have unmet expectations.
Surgeons must work to achieve realistic patient expectations pre-operatively,
and therefore, improve patient satisfaction post-operatively. Cite this article:
In order to achieve satisfactory reduction of
complex distal humeral fractures, adequate exposure of the fracture fragments
and the joint surface is required. Several surgical exposures have
been described for distal humeral fractures. We report our experience
using the anconeus pedicle olecranon flip osteotomy approach. This
involves detachment of the triceps along with a sliver of olecranon,
which retains the anconeus pedicle. We report the use of this approach
in ten patients (six male, four female) with a mean age of 38.4
years (28 to 51). The mean follow-up was 15 months (12 to 18) with
no loss to follow-up. Elbow function was graded using the Mayo Score.
The results were excellent in four patients, good in five and fair
in one patient. The mean time to both fracture and osteotomy union
was 10.6 weeks (8 to 12) and 7.1 weeks (6 to 8), respectively. We
found this approach gave reliably good exposure for these difficult
fractures enabling anatomical reduction and bicondylar plating without
complications. Cite this article:
Patients with transfemoral amputation (TFA) often
experience problems related to the use of socket-suspended prostheses.
The clinical development of osseointegrated percutaneous prostheses
for patients with a TFA started in 1990, based on the long-term
successful results of osseointegrated dental implants. Between1999 and 2007, 51 patients with 55 TFAs were consecutively
enrolled in a prospective, single-centre non-randomised study and
followed for two years. The indication for amputation was trauma
in 33 patients (65%) and tumour in 12 (24%). A two-stage surgical
procedure was used to introduce a percutaneous implant to which
an external amputation prosthesis was attached. The assessment of
outcome included the use of two self-report questionnaires, the
Questionnaire for Persons with a Transfemoral Amputation (Q-TFA)
and the Short-Form (SF)-36. The cumulative survival at two years’ follow-up was 92%. The
Q-TFA showed improved prosthetic use, mobility, global situation
and fewer problems (all p <
0.001). The physical function SF-36
scores were also improved (p <
0.001). Superficial infection
was the most frequent complication, occurring 41 times in 28 patients
(rate of infection 54.9%). Most were treated effectively with oral
antibiotics. The implant was removed in four patients because of loosening
(three aseptic, one infection). Osseointegrated percutaneous implants constitute a novel form
of treatment for patients with TFA. The high cumulative survival
rate at two years (92%) combined with enhanced prosthetic use and
mobility, fewer problems and improved quality of life, supports
the ‘revolutionary change’ that patients with TFA have reported
following treatment with osseointegrated percutaneous prostheses. Cite this article:
The June 2014 Wrist &
Hand Roundup360 looks at: aart throwing not quite as we thought; two-gear, four-bar linkage in the wrist?; assessing outcomes in distal radial fractures; gold standard Swanson’s?; multistrand repairs of unclear benefit in flexor tendon release; for goodness’ sake, leave the thumb alone in scaphoid fractures; horizons in carpal tunnel surgery; treading the Essex-Lopresti tightrope; wrist replacement in trauma? and radial shortening reliable in the long term for Kienbock’s disease
The June 2014 Hip &
Pelvis Roundup360 looks at: Modular femoral necks: early signs are not good; is corrosion to blame for modular neck failures; metal-on-metal is not quite a closed book; no excess failures in fixation of displaced femoral neck fractures; noise no problem in hip replacement; heterotopic ossification after hip arthroscopy: are NSAIDs the answer?; thrombotic and bleeding events surprisingly low in total joint replacement; and the elephant in the room: complications and surgical volume.
We studied, ten patients (11 elbows) who had
undergone 14 allograft-prosthesis composite reconstructions following
failure of a previous total elbow replacement with massive structural
bone loss. There were nine women and one man with a mean age of
64 years (40 to 84), who were reviewed at a mean of 75 months (24
to 213). One patient developed a deep infection after 26 months
and had the allograft-prosthesis composite removed, and two patients
had mild pain. The median flexion-extension arc was 100° (95% confidence
interval (CI) 76° to 124°). With the exception of the patient who
had the infected failure, all the patients could use their elbows
comfortably without splints or braces for activities of daily living.
The mean Mayo Elbow Performance Index improved from 9.5 (95% CI
4.4 to 14.7) pre-operatively to 74 (95% CI 62.4 to 84.9) at final
review. Radiologically, the rate of partial resorption was similar in
the humeral and ulnar allografts (three of six and four of eight,
respectively; p >
0.999). The patterns of resorption, however, were
different. Union at the host-bone-allograft junction was also different
between the humeral and ulnar allografts (one of six and seven of
eight showing union, respectively; p = 0.03). At medium-term follow-up, allograft-prosthesis composite reconstruction
appears to be a useful salvage technique for failed elbow replacements
with massive bone loss. The effects of allograft resorption and
host-bone-allograft junctional union on the longevity of allograft-prosthesis
composite reconstruction, however, remain unknown, and it is our
view that these patients should remain under long-term regular review.
Mobile-bearing unicompartmental knee replacements
(UKRs) with a flat tibial plateau have not performed well in the
lateral compartment, owing to a high dislocation rate. This led
to the development of the Domed Lateral Oxford UKR (Domed OUKR)
with a biconcave bearing. The aim of this study was to assess the
survival and clinical outcomes of the Domed OUKR in a large patient
cohort in the medium term. We prospectively evaluated 265 consecutive knees with isolated
disease of the lateral compartment and a mean age at surgery of
64 years (32 to 90). At a mean follow-up of four years ( The Domed Lateral OUKR gives good clinical outcomes, low re-operation
and revision rates and a low dislocation rate in patients with isolated
lateral compartmental disease, in the hands of the designer surgeons. Cite this article:
We have evaluated the clinical effectiveness
of a metal resurfacing inlay implant for osteochondral defects of
the medial talar dome after failed previous surgical treatment.
We prospectively studied 20 consecutive patients with a mean age
of 38 years (20 to 60), for a mean of three years (2 to 5) post-surgery.
There was statistically significant reduction of pain in each of
four situations (i.e., rest, walking, stair climbing and running;
p ≤ 0.01). The median American Orthopaedic Foot and Ankle Society
ankle-hindfoot score improved from 62 (interquartile range (IQR)
46 to 72) pre-operatively to 87 (IQR 75 to 95) at final follow-up
(p <
0.001). The Foot and Ankle Outcome Score improved on all
subscales (p ≤ 0.03). The mean Short-Form 36 physical component
scale improved from 36 (23 to 50) pre-operatively to 45 (29 to 55)
at final follow-up (p = 0.001); the mental component scale did not
change significantly. On radiographs, progressive degenerative changes
of the opposing tibial plafond were observed in two patients. One
patient required additional surgery for the osteochondral defect.
This study shows that a metal implant is a promising treatment for
osteochondral defects of the medial talar dome after failed previous
surgery. Cite this article:
The lateral compartment is predominantly affected
in approximately 10% of patients with osteoarthritis of the knee. The
anatomy, kinematics and loading during movement differ considerably
between medial and lateral compartments of the knee. This in the
main explains the relative protection of the lateral compartment
compared with the medial compartment in the development of osteoarthritis.
The aetiology of lateral compartment osteoarthritis can be idiopathic,
usually affecting the femur, or secondary to trauma commonly affecting
the tibia. Surgical management of lateral compartment osteoarthritis
can include osteotomy, unicompartmental knee replacement and total
knee replacement. This review discusses the biomechanics, pathogenesis
and development of lateral compartment osteoarthritis and its management. Cite this article:
The Motec cementless modular metal-on-metal ball-and-socket
wrist arthroplasty was implanted in 16 wrists with scaphoid nonunion
advanced collapse (SNAC; grades 3 or 4) and 14 wrists with scapholunate
advanced collapse (SLAC) in 30 patients (20 men) with severe (grades
3 or 4) post-traumatic osteoarthritis of the wrist. The mean age of
the patients was 52 years (31 to 71). All prostheses integrated
well radiologically. At a mean follow-up of 3.2 years (1.1 to 6.1)
no luxation or implant breakage occurred. Two wrists were converted
to an arthrodesis for persistent pain. Loosening occurred in one
further wrist at five years post-operatively. The remainder demonstrated close
bone–implant contact. The clinical results were good, with markedly
decreased Disabilities of the Arm Shoulder and Hand (DASH) and pain
scores, and increased movement and grip strength. No patient used
analgesics and most had returned to work. Good short-term function was achieved using this wrist arthroplasty
in a high-demand group of patients with post-traumatic osteoarthritis.