Bone loss in the proximal tibia and distal femur
is frequently encountered in revision knee replacement surgery.
The various options for dealing with this depend on the extent of
any bone loss. We present our results with the use of cementless
metaphyseal metal sleeves in 103 patients (104 knees) with a mean
follow-up of 43 months (30 to 65). At final follow-up, sleeves in
102 knees had good osseointegration. Two tibial sleeves were revised
for loosening, possibly due to infection. The average pre-operative Oxford Knee Score was 23 (11 to 36)
and this improved to 32 (15 to 46) post-operatively. These early
results encourage us to continue with the technique and monitor
the outcomes in the long term. Cite this article:
We report our experience of using a computer
navigation system to aid resection of malignant musculoskeletal tumours
of the pelvis and limbs and, where appropriate, their subsequent
reconstruction. We also highlight circumstances in which navigation
should be used with caution. We resected a musculoskeletal tumour from 18 patients (15 male,
three female, mean age of 30 years (13 to 75) using commercially
available computer navigation software (Orthomap 3D) and assessed
its impact on the accuracy of our surgery. Of nine pelvic tumours,
three had a biological reconstruction with extracorporeal irradiation,
four underwent endoprosthetic replacement (EPR) and two required
no bony reconstruction. There were eight tumours of the bones of
the limbs. Four diaphyseal tumours underwent biological reconstruction.
Two patients with a sarcoma of the proximal femur and two with a
sarcoma of the proximal humerus underwent extra-articular resection
and, where appropriate, EPR. One soft-tissue sarcoma of the adductor
compartment which involved the femur was resected and reconstructed
using an EPR. Computer navigation was used to aid reconstruction
in eight patients. Histological examination of the resected specimens revealed tumour-free
margins in all patients. Post-operative radiographs and CT showed
that the resection and reconstruction had been carried out as planned
in all patients where navigation was used. In two patients, computer
navigation had to be abandoned and the operation was completed under
CT and radiological control. The use of computer navigation in musculoskeletal oncology allows
accurate identification of the local anatomy and can define the
extent of the tumour and proposed resection margins. Furthermore,
it helps in reconstruction of limb length, rotation and overall
alignment after resection of an appendicular tumour. Cite this article:
The treatment of infected nonunions is difficult.
Antibiotic cement-coated (ACC) rods provide stability as well as delivering
antibiotics. We conducted a review of 110 infected nonunions treated
with ACC rods. Patients were divided into two groups: group A (67
patients) with an infected arthrodesis, and group B (43 patients)
with an infected nonunion in a long bone. In group A, infected arthrodesis,
the success rate after the first procedure was 38/67 (57%), 29/67
(43%) required further surgery for either control of infection or
non-union. At last follow-up, five patients required amputation,
representing a limb salvage rate of 62/67 (93%) overall. In all,
29/67 (43%) presented with a bone defect with a mean size of 6.78
cm (2 to 25). Of those with a bone defect, 13/29 (45%) required
further surgery and had a mean size of defect of 7.2 cm (3.5 to
25). The cultures were negative in 17/67 (26%) and the most common
organism cultured was methicillin-resistant Cite this article:
Improvements in the surgical technique of total
knee replacement (TKR) are continually being sought. There has recently
been interest in three-dimensional (3D) pre-operative planning using
magnetic resonance imaging (MRI) and CT. The 3D images are increasingly
used for the production of patient-specific models, surgical guides
and custom-made implants for TKR. The users of patient-specific instrumentation (PSI) claim that
they allow the optimum balance of technology and conventional surgery
by reducing the complexity of conventional alignment and sizing
tools. In this way the advantages of accuracy and precision claimed
by computer navigation techniques are achieved without the disadvantages
of additional intra-operative inventory, new skills or surgical
time. This review describes the terminology used in this area and debates
the advantages and disadvantages of PSI.
We report a 12- to 15-year implant survival assessment
of a prospective single-surgeon series of Birmingham Hip Resurfacings
(BHRs). The earliest 1000 consecutive BHRs including 288 women (335
hips) and 598 men (665 hips) of all ages and diagnoses with no exclusions
were prospectively followed-up with postal questionnaires, of whom
the first 402 BHRs (350 patients) also had clinical and radiological
review. Mean follow-up was 13.7 years (12.3 to 15.3). In total, 59 patients
(68 hips) died 0.7 to 12.6 years following surgery from unrelated
causes. There were 38 revisions, 0.1 to 13.9 years (median 8.7)
following operation, including 17 femoral failures (1.7%) and seven
each of infections, soft-tissue reactions and other causes. With
revision for any reason as the end-point Kaplan–Meier survival analysis
showed 97.4% (95% confidence interval (CI) 96.9 to 97.9) and 95.8%
(95% CI 95.1 to 96.5) survival at ten and 15 years, respectively.
Radiological assessment showed 11 (3.5%) femoral and 13 (4.1%) acetabular
radiolucencies which were not deemed failures and one radiological
femoral failure (0.3%). Our study shows that the performance of the BHR continues to
be good at 12- to 15-year follow-up. Men have better implant survival
(98.0%; 95% CI 97.4 to 98.6) at 15 years than women (91.5%; 95%
CI 89.8 to 93.2), and women <
60 years (90.5%; 95% CI 88.3 to
92.7) fare worse than others. Hip dysplasia and osteonecrosis are
risk factors for failure. Patients under 50 years with osteoarthritis
fare best (99.4%; 95% CI 98.8 to 100 survival at 15 years), with
no failures in men in this group. Cite this article:
The August 2012 Oncology Roundup360 looks at: prolonged symptom duration; peri-operative mortality and above-knee amputation; giant cell tumour of the spine; surgical resection for Ewing’s sarcoma; intercalary allograft reconstruction of the femur for tumour defects; and an induced membrane technique for large bone defects.
We investigated whether the extension gap in total knee replacement (TKR) would be changed when the femoral component was inserted. The extension gap was measured with and without the femoral component in place in 80 patients with varus osteoarthritis undergoing posterior-stabilised TKR. The effect of a post-operative increase in the size of the femoral posterior condyles was also evaluated. The results showed that placement of the femoral component significantly reduced the medial and lateral extension gaps by means of 1.0 mm and 0.9 mm, respectively (p <
0.0001). The extension gap was reduced when a larger femoral component was selected relative to the thickness of the resected posterior condyle. When the post-operative posterior lateral condyle was larger than that pre-operatively, 17 of 41 knees (41%) showed a decrease in the extension gap of >
2.0 mm. When a specially made femoral trial component with a posterior condyle enlarged by 4 mm was tested, the medial and lateral extension gaps decreased further by means of 2.1 mm and 2.8 mm, respectively. If the thickness of the posterior condyle is expected to be larger than that pre-operatively, it should be recognised that the extension gap is likely to be altered. This should be taken into consideration when preparing the extension gap.
We aimed to obtain anthropometric data on Korean
knees and to compare these with data on commonly available total
knee arthroplasties (TKAs). The dimensions of the femora and tibiae
of 1168 knees were measured intra-operatively. The femoral components
were found to show a tendency toward mediolateral (ML) under-coverage
in small femurs and ML overhang in the large femurs. The ML under-coverage
was most prominent for the small prostheses. The ML/anteroposterior
(ML/AP) ratio of Korean tibiae was greater than that of tibial components. This study shows that, for different reasons, current TKAs do
not provide a reasonable fit for small or large Korean knees, and
that the ‘gender-specific’ and ‘stature-specific’ components help
for large Korean femurs but offer less satisfactory fits for small
femurs. Specific modifications of prostheses are needed for Asian
knees.
Because posterior cruciate ligament (PCL) resection makes flexion
gaps wider in total knee replacement (TKR), preserving or sacrificing
a PCL affects the gap equivalence; however, there are no criteria
for the PCL resection that consider gap situations of each knee.
This study aims to investigate gap characteristics of knees and
to consider the criteria for PCL resection. The extension and flexion gaps were measured, first with the
PCL preserved and subsequently with the PCL removed (in cases in
which posterior substitute components were selected). The PCL preservation
or sacrifice was solely determined by the gap measurement results,
without considering other functions of the PCL such as ‘roll back.’Objectives
Methods
We determined the efficacy of a devitalised autograft
(n = 13) and allograft (n = 16) cortical strut bone graft combined
with long-stem endoprosthetic reconstruction in the treatment of
massive tumours of the lower limb. A total of 29 patients (18 men:11
women, mean age 20.1 years (12 to 45) with a ratio of length of
resection to that of the whole prosthesis of >
50% were treated
between May 2003 and May 2012. The mean follow-up was 47 months
(15 to 132). The stem of the prosthesis was introduced through bone
graft struts filled with cement, then cemented into the residual
bone. Bone healing was achieved in 23 patients (86%). The mean Musculoskeletal
Tumour Society functional score was 85% (57 to 97). The five-year
survival rate of the endoprostheses was 81% (95% confidence intervals
67.3 to 92.3). The mean length of devitalised autografts and allografts
was 8.6 cm (5 to 15), which increased the ratio of the the length
of the stem of the prosthesis to that of the whole length of the
prosthesis from a theoretical 35% to an actual 55%. Cortical strut bone grafting and long-stem endoprosthetic reconstruction
is an option for treating massive segmental defects following resection
of a tumour in the lower limb. Patients can regain good function
with a low incidence of aseptic loosening. The strut graft and the
residual bone together serve as a satisfactory bony environment
for a revision prosthesis, if required, once union is achieved. Cite this article:
We reviewed the outcome of 69 uncemented, custom-made,
distal femoral endoprosthetic replacements performed in 69 patients
between 1994 and 2006. There were 31 women and 38 men with a mean
age at implantation of 16.5 years (5 to 37). All procedures were
performed for primary malignant bone tumours of the distal femur.
At a mean follow-up of 124.2 months (4 to 212), 53 patients were
alive, with one patient lost to follow-up. All nine implants (13.0%)
were revised due to aseptic loosening at a mean of 52 months (8
to 91); three implants (4.3%) were revised due to fracture of the
shaft of the prosthesis and three patients (4.3%) had a peri-prosthetic
fracture. Bone remodelling associated with periosteal cortical thinning
adjacent to the uncemented intramedullary stem was seen in 24 patients
but this did not predispose to failure. All aseptically loose implants
in this series were diagnosed to be loose within the first five
years. The results from this study suggest that custom-made uncemented
distal femur replacements have a higher rate of aseptic loosening
compared to published results for this design when used with cemented
fixation. Loosening of uncemented replacements occurs early indicating
that initial fixation of the implant is crucial. Cite this article:
The December 2013 Oncology Roundup360 looks at: Peri-articular resection fraught with complications; Navigated margins; Skeletal tumours and thromboembolism; Conditional survival in Ewing’s sarcoma; Reverse shoulders and tumour; For how long should we follow up sarcoma patients?; and already metastasised?
We performed a randomised controlled trial comparing
computer-assisted surgery (CAS) with conventional surgery (CONV)
in total knee replacement (TKR). Between 2009 and 2011 a total of
192 patients with a mean age of 68 years (55 to 85) with osteoarthritis
or arthritic disease of the knee were recruited from four Norwegian
hospitals. At three months follow-up, functional results were marginally
better for the CAS group. Mean differences (MD) in favour of CAS
were found for the Knee Society function score (MD: 5.9, 95% confidence
interval (CI) 0.3 to 11.4, p = 0.039), the Knee Injury and Osteoarthritis
Outcome Score (KOOS) subscales for ‘pain’ (MD: 7.7, 95% CI 1.7 to
13.6, p = 0.012), ‘sports’ (MD: 13.5, 95% CI 5.6 to 21.4, p = 0.001)
and ‘quality of life’ (MD: 7.2, 95% CI 0.1 to 14.3, p = 0.046).
At one-year follow-up, differences favouring CAS were found for
KOOS ‘sports’ (MD: 11.0, 95% CI 3.0 to 19.0, p = 0.007) and KOOS
‘symptoms’ (MD: 6.7, 95% CI 0.5 to 13.0, p = 0.035). The use of
CAS resulted in fewer outliers in frontal alignment (>
3° malalignment),
both for the entire TKR (37.9% Cite this article:
This review is aimed at clinicians appraising
preclinical trauma studies and researchers investigating compromised bone
healing or novel treatments for fractures. It categorises the clinical
scenarios of poor healing of fractures and attempts to match them
with the appropriate animal models in the literature. We performed an extensive literature search of animal models
of long bone fracture repair/nonunion and grouped the resulting
studies according to the clinical scenario they were attempting
to reflect; we then scrutinised them for their reliability and accuracy
in reproducing that clinical scenario. Models for normal fracture repair (primary and secondary), delayed
union, nonunion (atrophic and hypertrophic), segmental defects and
fractures at risk of impaired healing were identified. Their accuracy
in reflecting the clinical scenario ranged greatly and the reliability
of reproducing the scenario ranged from 100% to 40%. It is vital to know the limitations and success of each model
when considering its application.
We aimed to determine the effect of surgical approach on the
histology of the femoral head following resurfacing of the hip. We performed a histological assessment of the bone under the
femoral component taken from retrieval specimens of patients having
revision surgery following resurfacing of the hip. We compared the
number of empty lacunae in specimens from patients who had originally
had a posterior surgical approach with the number in patients having alternative
surgical approaches.Objectives
Methods
The April 2013 Oncology Roundup360 looks at: the margin for error; new money for old risks; hindquarter amputation; custom tumour jigs; preserving the tibial epiphysis; how long is long enough?; genomics and radiation-induced bone tumours; and India ink.
The role of modular tibial implants in total knee replacement is not fully defined. We performed a prospective randomised controlled clinical trial using radiostereophotogrammetric analysis to compare the performance of an all-polyethylene tibia with a metal-backed cruciate-retaining condylar design, PFC-∑ total knee replacement for up to 24 months. There were 51 patients who were randomised into two treatment groups. There were 10 subsequent withdrawals, leaving 21 all-polyethylene and 20 metal-backed tibial implants. No patient was lost to follow-up. There were no significant demographic differences between the groups. At two years one metal-backed implant showed migration >
1 mm, but no polyethylene implant reached this level. There was a significant increase in the SF-12 and Oxford knee scores after operation in both groups. In an uncomplicated primary total knee replacement the all-polyethylene PFC-∑ tibial prosthesis showed no statistical difference in migration from that of the metal-backed counterpart. There was no difference in the clinical results as assessed by the SF-12, the Oxford knee score, alignment or range of movement at 24 months, although these assessment measures were not statistically powered in this study.
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.
We retrospectively reviewed 101 consecutive patients
with 114 femoral tumours treated by massive bone allograft at our
institution between 1986 and 2005. There were 49 females and 52
males with a mean age of 20 years (4 to 74). At a median follow-up
of 9.3 years (2 to 19.8), 36 reconstructions (31.5%) had failed.
The allograft itself failed in 27 reconstructions (24%). Mechanical complications such as delayed union, fracture and
failure of fixation were studied. The most adverse factor on the
outcome was the use of intramedullary nails, followed by post-operative
chemotherapy, resection length >
17 cm and age >
18 years at the
time of intervention. The simultaneous use of a vascularised fibular
graft to protect the allograft from mechanical complications improved
the outcome, but the use of intramedullary cementing was not as
successful. In order to improve the strength of the reconstruction and to
advance the biology of host–graft integration, we suggest avoiding
the use of intramedullary nails and titanium plates, but instead
using stainless steel plates, as these gave better results. The
use of a supplementary vascularised fibular graft should be strongly
considered in adult patients with resection >
17 cm and in those
who require post-operative chemotherapy.
The Bologna–Oxford (BOX) total ankle replacement
(TAR) was developed with the aim of achieving satisfactory pain-free
movement of the ankle. To date, only one single multicentre study
has reported its clinical results. The aim of this study was to
conduct an independent review of its mid-term results. We retrospectively reviewed a total of 60 prospectively followed
patients in whom 62 BOX TARs had been implanted between 2004 and
2008. We used the American Orthopedic Foot and Ankle Society (AOFAS)
score to assess the clinical results. Standardised radiographs taken
at the time of final follow-up were analysed by two observers. The
overall survival was 91.9% at a mean follow-up of 42.5 months (24
to 71). The mean AOFAS score had improved from 35.1 points (