1. The effect of immobilisation on bone formation has been investigated in the rat. As chlortetracycline has the property of being deposited preferentially in areas of newly deposited bone, its uptake can be used as a reflection of osseous formation. 2. One hind limb of albino rats was immobilised either by section of the second, third and fourth lumbar nerve trunks or by section of tendo calcaneus and ligamentum patellae. The incorporation of chlortetracycline was determined quantitatively in the femur and tibia of both hind limbs at intervals after immobilisation. 3. Tetracycline uptake is expressed in terms of bone weight, this being most important in order to obtain correct values. 4. A comparison between the tetracycline uptake and the weight of the bones gives information about the rate of bone destruction. 5. In animals immobilised by nerve section three phases can be distinguished: a first phase with diminished bone formation, a second with increased formation and increased destruction and a third phase with diminished bone formation. Both mechanisms, decreased formation and increased destruction, are therefore important in the production of immobilisation osteoporosis; their relative importance depending upon the duration of the immobilisation. 6. In animals immobilised by tendon section the mechanical function becomes restored in the second week as a result of healing: this explains the rapid compensation for the initial loss of weight of the bones accompanied by a marked increase in tetracycline uptake. 7. These results are discussed and compared with information in the literature. Variations in bone formation and destruction rates with time could explain the varied results reported by other authors.
The surgical treatment of tuberculosis (TB) of the spine consists
of debridement and reconstruction of the anterior column. Loss of
correction is the most significant challenge. Our aim was to report
the outcome of single-stage posterior surgery using bone allografts
in the management of this condition. The study involved 24 patients with thoracolumbar TB who underwent
single-stage posterior spinal surgery with a cortical bone allograft
for anterior column reconstruction and posterior instrumentation
between 2008 and 2015. A unilateral approach was used for 21 patients
with active TB, and a bilateral approach with decompression and closing-opening
wedge osteotomy was used for three patients with healed TB.Aims
Patients and Methods
Cancellous allograft bone chips are commonly
used in the reconstruction of defects in bone after removal of benign tumours.
We investigated the MRI features of grafted bone chips and their
change over time, and compared them with those with recurrent tumour.
We retrospectively reviewed 66 post-operative MRIs from 34 patients
who had undergone curettage and grafting with cancellous bone chips
to fill the defect after excision of a tumour. All grafts showed
consistent features at least six months after grafting: homogeneous
intermediate or low signal intensities with or without scattered
hyperintense foci (speckled hyperintensities) on T1 images; high
signal intensities with scattered hypointense foci (speckled hypointensities)
on T2 images, and peripheral rim enhancement with or without central
heterogeneous enhancements on enhanced images.
We describe a new technique of reconstruction of the deficient acetabulum in cementless total hip arthroplasty. The outer iliac table just above the deficient acetabulum is osteotomised and slid downwards. We have termed this an iliac sliding graft. Between October 1997 and November 2001, cementless total hip arthroplasty with an iliac sliding graft was performed on 19 patients (19 hips) with acetabular dysplasia. The mean follow-up was 3.4 years (2 to 6). The mean pre-operative Harris hip score was 45.1 which improved significantly to 85.3 at the time of the final follow-up. No patient had post-operative abductor dysfunction.
There is no consensus regarding optimum timing and frequency of ultrasound (US) for monitoring response to Pavlik harness (PH) treatment in developmental dysplasia of the hip (DDH). The purpose of our study was to determine if a limited-frequency hip US assessment had an adverse effect on treatment outcomes compared to traditional comprehensive US monitoring. This study was a single-centre noninferiority randomized controlled trial. Infants aged under six months whose hips were reduced and centred in the harness at initiation of treatment (stable dysplastic or subluxable), or initially decentred (subluxated or dislocated) but reduced and centred within four weeks of PH treatment, were randomized to our current standard US monitoring protocol (every clinic visit) or to a limited-frequency US protocol (US only at end of treatment). Groups were compared based on α angle and femoral head coverage at the end of PH treatment, acetabular indices, and International Hip Dysplasia Institute (IHDI) grade on one-year follow-up radiographs.Aims
Methods
Infection of a total hip replacement (THR) requires component removal and thorough local debridement. Usually, long-term antibiotic treatment in conjunction with a two-stage revision is required. This may take several months. One-stage revision using antibiotic-loaded cement has not gained widespread use, although the clinical and economic advantages are obvious. Allograft bone may be impregnated with high levels of antibiotics, and in revision of infected THR, act as a carrier providing a sustained high local concentration. We performed 37 one-stage revision of infected THRs, without the use of cement. There were three hips which required further revision because of recurrent infection, the remaining 34 hips (92%) stayed free from infection and stable at a mean follow-up of 4.4 years (2 to 8). No adverse effects were identified.
Femoral impaction bone allografting has been developed as a means of restoring bone stock in revision total hip replacement. We report the results of 75 consecutive patients (75 hips) with a mean age of 68 years (35 to 87) who underwent impaction grafting using the Exeter collarless, polished, tapered femoral stem between 1992 and 1998. The mean follow-up period was 10.5 years (6.3 to 14.1). The median pre-operative bone defect score was 3 (interquartile range (IQR) 2 to 3) using the Endo-Klinik classification. The median subsidence at one year post-operatively was 2 mm (IQR 1 to 3). At the final review the median Harris hip score was 80.6 (IQR 67.6 to 88.9) and the median subsidence 2 mm (IQR 1 to 4).
Neglected fractures of the femoral neck, common in young adults in underdeveloped countries, may be complicated by nonunion or avascular necrosis (AVN). We treated 52 cases by open reduction, fixation by compression screw and a free fibular graft. The mean delay between injury and operation was 5.1 months. Of 40 fractures assessed at a mean of 58.8 months (24 to 153), 38 were found to be united and two, owing to surgical errors, were not. Seven of eight heads which were avascular before operation revascularised without collapse, while seven others developed AVN after the procedure. At the last follow-up considerable collapse was apparent in five femoral heads, and 11 hips had developed coxa vara. The fibular graft had fractured in four cases. The hip had been penetrated by the screw in six cases and by the graft in three. Hip function was excellent in seven patients, good in 21 and fair in seven. Five patients had poor results.
The aim of this study was to evaluate antegrade autologous bone
grafting with the preservation of articular cartilage in the treatment
of symptomatic osteochondral lesions of the talus with subchondral
cysts. The study involved seven men and five women; their mean age was
35.9 years (14 to 70). All lesions included full-thickness articular
cartilage extending through subchondral bone and were associated
with subchondral cysts. Medial lesions were exposed through an oblique
medial malleolar osteotomy, and one lateral lesion was exposed by
expanding an anterolateral arthroscopic portal. After refreshing
the subchondral cyst, it was grafted with autologous cancellous
bone from the distal tibial metaphysis. The fragments of cartilage
were fixed with 5-0 nylon sutures to the surrounding cartilage.
Function was assessed at a mean follow-up of 25.3 months (15 to
50), using the American Orthopaedic Foot and Ankle Society (AOFAS)
ankle-hindfoot outcome score. The radiological outcome was assessed
using MRI and CT scans.Aims
Patients and Methods
The purpose of this retrospective study was to differentiate
between the MRI features of normal post-operative change and those
of residual or recurrent disease after intralesional treatment of
an atypical cartilage tumour (ACT)/grade I chondrosarcoma. We reviewed the case notes, radiology and histology of 75 patients,
who had been treated for an ACT/grade I chondrosarcoma by curettage,
phenolisation and bone allografting between 1994 and 2005. The first
post-operative Gd-enhanced MRI scan was carried out within one year
of surgery. Patients had a minimum of two scans and a mean follow-up
of 72 months (13 to 169). Further surgery was undertaken in cases
of suspected recurrence.Aims
Patients and Methods
Femoral impaction bone grafting was first developed in 1987 using
morselised cancellous bone graft impacted into the femoral canal
in combination with a cemented, tapered, polished stem. We describe
the evolution of this technique and instrumentation since that time. Between 1987 and 2005, 705 revision total hip arthroplasties
(56 bilateral) were performed with femoral impaction grafting using
a cemented femoral stem. All surviving patients were prospectively
followed for a mean of 14.7 years (9.8 to 28.3) with no loss to
follow-up. By the time of the final review, 404 patients had died.Aims
Patients and Methods
We describe the results of 81 consecutive revision
total hip replacements with impaction grafting in 79 patients using
a collared polished chrome–cobalt stem, customised in length according
to the extent of distal bone loss. Our hypothesis was that the features
of this stem would reduce the rate of femoral fracture and subsidence
of the stem. The mean follow-up was 12 years (8 to 15). No intra-operative
fracture or significant subsidence occurred. Only one patient suffered
a post-operative diaphyseal fracture, which was associated with
a fall. All but one femur showed incorporation of the graft. No
revision for aseptic loosening was recorded. The rate of survival of the femoral component at 12 years, using
further femoral revision as the endpoint, was 100% (95% confidence
interval (CI) 95.9 to 100), and at nine years using re-operation
for any reason as the endpoint, was 94.6% (95% CI 92.0 to 97.2). These results suggest that a customised cemented polished stem
individually adapted to the extent of bone loss and with a collar
may reduce subsidence and the rate of fracture while maintaining
the durability of the fixation.
We present the results of 62 consecutive acetabular
revisions using impaction bone grafting and a cemented polyethylene
acetabular component in 58 patients (13 men and 45 women) after
a mean follow-up of 27 years (25 to 30). All patients were prospectively
followed. The mean age at revision was 59.2 years (23 to 82). We performed Kaplan–Meier (KM) analysis and also a Competing
Risk (CR) analysis because with long-term follow-up, the presence
of a competing event (i.e. death) prevents the occurrence of the
endpoint of re-revision. A total of 48 patients (52 hips) had died or had been re-revised
at final review in March 2011. None of the deaths were related to
the surgery. The mean Harris hip score of the ten surviving hips
in ten patients was 76 points (45 to 99). The KM survivorship at 25 years for the endpoint ‘re-revision
for any reason’ was 58.0% (95% confidence interval (CI) 38 to 73)
and for ‘re-revision for aseptic loosening’ 72.1% (95% CI 51 to
85). With the CR analysis we calculated the KM analysis overestimates
the failure rate with respectively 74% and 93% for these endpoints.
The current study shows that acetabular impaction bone grafting
revisions provide good clinical results at over 25 years. Cite this article:
Bone allografts can be used in any kind of surgery involving bone from minor defects to major bone loss after tumour resection. This review describes the various types of bone grafts and the current knowledge on bone allografts, from procurement and preparation to implantation. The surgical conditions for optimising the incorporation of bone are outlined, and surgeon expectations from a bone allograft discussed.
We hypothesised that cells obtained via a Reamer–Irrigator–Aspirator
(RIA) system retain substantial osteogenic potential and are at
least equivalent to graft harvested from the iliac crest. Graft
was harvested using the RIA in 25 patients (mean age 37.6 years
(18 to 68)) and from the iliac crest in 21 patients (mean age 44.6
years (24 to 78)), after which ≥ 1 g of bony particulate graft material
was processed from each. Initial cell viability was assessed using Trypan
blue exclusion, and initial fluorescence-activated cell sorting
(FACS) analysis for cell lineage was performed. After culturing
the cells, repeat FACS analysis for cell lineage was performed and
enzyme-linked immunosorbent assay (ELISA) for osteocalcin, and Alizarin
red staining to determine osteogenic potential. Cells obtained via
RIA or from the iliac crest were viable and matured into mesenchymal
stem cells, as shown by staining for the specific mesenchymal antigens
CD90 and CD105. For samples from both RIA and the iliac crest there
was a statistically significant increase in bone production (both
p <
0.001), as demonstrated by osteocalcin production after induction. Medullary autograft cells harvested using RIA are viable and
osteogenic. Cell viability and osteogenic potential were similar
between bone grafts obtained from both the RIA system and the iliac
crest. Cite this article:
Structural allografts may be used to manage uncontained
bone defects in revision total knee replacement (TKR). However,
the availability of cadaver grafts is limited in some areas of Asia.
The aim of this study was to evaluate the mid-term outcome of the
use of femoral head allografts for the reconstruction of uncontained
defects in revision TKR, focusing on complications related to the
graft. We retrospectively reviewed 28 patients (30 TKRs) with Anderson
Orthopaedic Research Institute (AORI) type 3 bone defects, who underwent
revision using femoral head allografts and stemmed components. The
mean number of femoral heads used was 1.7 (1 to 3). The allograft–host
junctions were packed with cancellous autograft. At a mean follow-up of 76 months (38 to 136) the mean American
Knee Society knee score improved from 37.2 (17 to 60) pre-operatively
to 90 (83 to 100) (p <
0.001). The mean function score improved
from 26.5 (0 to 50) pre-operatively to 81 (60 to 100) (p <
0.001).
All the grafts healed to the host bone. The mean time to healing
of the graft was 6.6 months
(4 to 16). There have been no complications of collapse of the graft,
nonunion, infection or implant loosening. No revision surgery was
required. The use of femoral head allografts in conjunction with a stemmed
component and autogenous bone graft in revision TKR in patients
with uncontained bone defects resulted in a high rate of healing
of the graft with minimal complications and a satisfactory outcome.
Longer follow-up is needed to observe the evolution of the graft. Cite this article:
We report the results of 62 hips in 62 patients
(17 males, 45 females) with mean age of 62.4 years (37 to 81), who underwent
revision of the acetabular component of a total hip replacement
due to aseptic loosening between May 2003 and November 2007. All
hips had a Paprosky type IIIa acetabular defect. Acetabular revision
was undertaken using a Procotyl E cementless oblong implant with
modular side plates and a hook combined with impaction allografting. At a mean follow-up of 60.5 months (36 to 94) with no patients
lost to follow-up and one died due to unrelated illness, the complication
rate was 38.7%. Complications included aseptic loosening (19 hips),
deep infection (3 hips), broken hook and side plate (one hip) and
a femoral nerve palsy (one hip). Further revision of the acetabular component
was required in 18 hips (29.0%) and a further four hips (6.4%) are
currently loose and awaiting revision. We observed unacceptably high rates of complication and failure
in our group of patients and cannot recommend this implant or technique.
Osteoporosis is common and the health and financial
cost of fragility fractures is considerable. The burden of cardiovascular
disease has been reduced dramatically by identifying and targeting
those most at risk. A similar approach is potentially possible in
the context of fragility fractures. The World Health Organization
created and endorsed the use of FRAX, a fracture risk assessment
tool, which uses selected risk factors to calculate a quantitative,
patient-specific, ten-year risk of sustaining a fragility fracture.
Treatment can thus be based on this as well as on measured bone
mineral density. It may also be used to determine at-risk individuals,
who should undergo bone densitometry. FRAX has been incorporated
into the national osteoporosis guidelines of countries in the Americas,
Europe, the Far East and Australasia. The United Kingdom National
Institute for Health and Clinical Excellence also advocates its
use in their guidance on the assessment of the risk of fragility
fracture, and it may become an important tool to combat the health
challenges posed by fragility fractures.
The clinical and radiological results of 50 consecutive acetabular reconstructions in 48 patients using impaction grafting have been retrospectively reviewed. A 1:1 mixture of frozen, ground irradiated bone graft and Apapore 60, a synthetic bone graft substitute, was used in all cases. There were 13 complex primary and 37 revision procedures with a mean follow-up of five years (3.4 to 7.6). The clinical survival rate was 100%, with improvements in the mean Harris Hip Scores for pain and function. Radiologically, 30 acetabular grafts showed evidence of incorporation, ten had radiolucent lines and two acetabular components migrated initially before stabilising. Acetabular reconstruction in both primary and revision surgery using a 1:1 mixture of frozen, ground, irriadiated bone and Apapore 60 appears to be a reliable method of managing acetabular defects. Longer follow-up will be required to establish whether this technique is as effective as using fresh-frozen allograft.