Coronal plane fractures of the posterior femoral
condyle, also known as Hoffa fractures, are rare. Lateral fractures are
three times more common than medial fractures, although the reason
for this is not clear. The exact mechanism of injury is likely to
be a vertical shear force on the posterior femoral condyle with
varying degrees of knee flexion. These fractures are commonly associated
with high-energy trauma and are a diagnostic and surgical challenge. Hoffa
fractures are often associated with inter- or supracondylar distal
femoral fractures and CT scans are useful in delineating the coronal
shear component, which can easily be missed. There are few recommendations
in the literature regarding the surgical approach and methods of
fixation that may be used for this injury. Non-operative treatment
has been associated with poor outcomes. The goals of treatment are
anatomical reduction of the articular surface with rigid, stable
fixation to allow early mobilisation in order to restore function.
A surgical approach that allows access to the posterior aspect of
the femoral condyle is described and the use of postero-anterior
lag screws with or without an additional buttress plate for fixation
of these difficult fractures. Cite this article:
We report the results at a mean of 24.3 years
(20 to 32) of 61 previously reported consecutive total hip replacements carried
out on 44 patients with severe congenital hip disease, performed
with reconstruction of the acetabulum with an impaction grafting
technique known as cotyloplasty. The mean age of the patients at
operation was 46.7 years (23 to 68) and all were women. The patients
were followed post-operatively for a mean of 24.3 years (20 to 32), using
the Merle d’Aubigné and Postel scoring system as modified by Charnley,
and with serial radiographs. At the time of the latest follow-up,
28 acetabular components had been revised because of aseptic loosening
at a mean of 15.9 years (6 to 26), and one at 40 days after surgery
because of repeated dislocations. The overall survival rate for aseptic
failure of the acetabular component at ten years was 93.1% (95%
confidence interval (CI) 86.5 to 96.7) when 53 hips were at risk,
and at 23 years was 56.1% (95% CI 49.4 to 62.8), when 22 hips remained
at risk. These long-term results are considered satisfactory for
the reconstruction of an acetabulum presenting with inadequate bone
stock and circumferential segmental defects. Cite this article:
Medial open-wedge high tibial osteotomy has been gaining popularity in recent years, but adequate supporting material is required in the osteotomy gap for early weight-bearing and rapid union. The purpose of this study was to investigate whether the implantation of a polycaprolactone-tricalcium phosphate composite scaffold wedge would enhance healing of the osteotomy in a micro pig model. We carried out open-wedge high tibial osteotomies in 12 micro pigs aged from 12 to 16 months. A scaffold wedge was inserted into six of the osteotomies while the other six were left open. Bone healing was evaluated after three and six months using plain radiographs, CT scans, measurement of the bone mineral density and histological examination. Complete bone union was obtained at six months in both groups. There was no collapse at the osteotomy site, loss of correction or failure of fixation in either group. Staining with haematoxylin and eosin demonstrated that there was infiltration of new bone tissue into the macropores and along the periphery of the implanted scaffold in the scaffold group. The CT scans and measurement of the bone mineral density showed that at six months specimens in the scaffold group had a higher bone mineral density than in the control group, although the implantation of the polycaprolactone-tricalcium phosphate composite scaffold wedge did not enhance healing of the osteotomy.
We prospectively evaluated the long-term outcome of 158 consecutive patients who underwent revision total hip replacement using uncemented computer-assisted design-computer-assisted manufacture femoral components. There were 97 men and 61 women. Their mean age was 63.1 years (34.6 to 85.9). The mean follow-up was 10.8 years (10 to 12). The mean Oxford, Harris and Western Ontario and McMaster hip scores improved from 41.1, 44.2 and 52.4 pre-operatively to 18.2, 89.3 and 12.3, respectively (p <
0.0001, for each). Six patients required further surgery. The overall survival of the femoral component was 97% (95% confidence interval 94.5 to 99.7). These results are comparable to those of previously published reports for revision total hip replacement using either cemented or uncemented components.
Various chemicals are commonly used as adjuvant treatment to surgery for giant-cell tumour (GCT) of bone. The comparative effect of these solutions on the cells of GCT is not known. In this study we evaluated the cytotoxic effect of sterile water, 95% ethanol, 5% phenol, 3% hydrogen peroxide (H2O2) and 50% zinc chloride (ZnCI2) on GCT monolayer tumour cultures which were established from six patients. The DNA content, the metabolic activity and the viability of the cultured samples of tumour cells were assessed at various times up to 120 hours after their exposure to these solutions. Equal cytotoxicity to the GCT monolayer culture was observed for 95% ethanol, 5% phenol, 3% H2O2 and 50% ZnCI2. The treated samples showed significant reductions in DNA content and metabolic activity 24 hours after treatment and this was sustained for up to 120 hours. The samples treated with sterile water showed an initial decline in DNA content and viability 24 hours after treatment, but the surviving cells were viable and had proliferated. No multinucleated cell formation was seen in these cultures. These results suggest that the use of chemical adjuvants other than water could help improve local control in the treatment of GCT of bone.
We describe a retrospective review of 38 cases of reconstruction following resection of the metaphysiodiaphysis of the lower limb for malignant bone tumours using free vascularised fibular grafts. The mean follow-up was for 7.6 years (0.4 to 18.4). The mean Musculoskeletal Tumor Society score was 27.2 (20 to 30). The score was significantly higher when the graft was carried out in a one-stage procedure after resection of the tumour rather than in two stages. Bony union was achieved in 89% of the cases. The overall mean time to union was 1.7 years (0.2 to 10.3). Free vascularised fibular transfer is a major operation with frequent, but preventable, complications which allows salvage of the limb with satisfactory functional results.
The December 2012 Trauma Roundup360 looks at: more is not always better, especially when its chemotherapy; new hope for skeletal metastasis; biopsy tracts; intra-operative imaging of sarcomas; curettage with adjuvant therapy; amputation and distal tibial osteosarcoma; and diaphyseal tibial tumours.
In this retrospective study we evaluated the method of acute shortening and distraction osteogenesis for the treatment of tibial nonunion with bone loss in 17 patients with a mean age of 36 years (10 to 58). The mean bone loss was 5.6 cm (3 to 10). In infected cases, we performed the treatment in two stages. The mean follow-up time was 43.5 months (24 to 96). The mean time in external fixation was 8.0 months (4 to 13) and the mean external fixator index was 1.4 months/cm (1.1 to 1.8). There was no recurrence of infection. The bone evaluation results were excellent in 16 patients and good in one, while functional results were excellent in 15 and good in two. The complication rate was 1.2 per patient. We conclude that acute shortening and distraction osteogenesis is a safe, reliable and successful method for the treatment of tibial nonunion with bone loss, with a shorter period of treatment and lower rate of complication.
The aim of this study was to report the pattern
of severe open diaphyseal tibial fractures sustained by military personnel,
and their orthopaedic–plastic surgical management. Cite this article:
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. Incorporation of bone graft was comparable with unimpregnated grafts. Antibiotic-impregnated allograft bone may enable reconstruction of bone stock, insertion of an uncemented implant and control of infection in a single operation in revision THR for infection.
In a randomised prospective study, 20 patients with intra-articular fractures of the distal radius underwent arthroscopically- and fluoroscopically-assisted reduction and external fixation plus percutaneous pinning. Another group of 20 patients with the same fracture characteristics underwent fluoroscopically-assisted reduction alone and external fixation plus percutaneous pinning. The patients were evaluated clinically and radiologically at follow-up of 24 months. The Disabilities of the Arm, Shoulder, and Hand (DASH) questionnaire and modified Mayo wrist score were used at 3, 9, 12 and 24 months postoperatively. In the arthroscopically- and fluoroscopically-assisted group, triangular fibrocartilage complex tears were found in 12 patients (60%), complete or incomplete scapholunate ligament tears in nine (45%), and lunotriquetral ligament tears in four (20%). They were treated either arthroscopically or by open operation. Patients who underwent arthroscopically- and fluoroscopically-assisted treatment had significantly better supination, extension and flexion at all time points than those who had fluoroscopically-assisted surgery. The mean DASH scores were similar for both groups at 24 months, whereas the difference in the mean modified Mayo wrist scores remained statistically significant. Although the groups are small, it is clear that the addition of arthroscopy to the fluoroscopically-assisted treatment of intra-articular distal radius fractures improves the outcome. Better treatment of associated intra-articular injuries might also have been a reason for the improved outcome.
The efficacy of β-tricalcium phosphate (β-TCP) loaded with bone morphogenetic protein-2 (BMP-2)-gene-modified bone-marrow mesenchymal stem cells (BMSCs) was evaluated for the repair of experimentally-induced osteonecrosis of the femoral head in goats. Bilateral early-stage osteonecrosis was induced in adult goats three weeks after ligation of the lateral and medial circumflex arteries and delivery of liquid nitrogen into the femoral head. After core decompression, porous β-TCP loaded with BMP-2 gene- or β-galactosidase (gal)-gene-transduced BMSCs was implanted into the left and right femoral heads, respectively. At 16 weeks after implantation, there was collapse of the femoral head in the untreated group but not in the BMP-2 or β-gal groups. The femoral heads in the BMP-2 group had a normal density and surface, while those in the β-gal group presented with a low density and an irregular surface. Histologically, new bone and fibrous tissue were formed in the macropores of the β-TCP. Sixteen weeks after implantation, lamellar bone had formed in the BMP-2 group, but there were some empty cavities and residual fibrous tissue in the β-gal group. The new bone volume in the BMP-2 group was significantly higher than that in the β-gal group. The maximum compressive strength and Young’s modulus of the repaired tissue in the BMP-2 group were similar to those of normal bone and significantly higher than those in the β-gal group. Our findings indicate that porous β-TCP loaded with BMP-2-gene-transduced BMSCs are capable of repairing early-stage, experimentally-induced osteonecrosis of the femoral head and of restoring its mechanical function.
Stems improve the mechanical stability of tibial
components in total knee replacement (TKR), but come at a cost of stress
shielding along their length. Their advantages include resistance
to shear, reduced tibial lift-off and increased stability by reducing
micromotion. Longer stems may have disadvantages including stress
shielding along the length of the stem with associated reduction
in bone density and a theoretical risk of subsidence and loosening, peri-prosthetic
fracture and end-of-stem pain. These features make long stems unattractive
in the primary TKR setting, but often desirable in revision surgery
with bone loss and instability. In the revision scenario, stems
are beneficial in order to convey structural stability to the construct
and protect the reconstruction of bony defects. Cemented and uncemented
long stemmed implants have different roles depending on the nature
of the bone loss involved. This review discusses the biomechanics of the design of tibial
components and stems to inform the selection of the component and
the technique of implantation.
External fixation of distal tibial fractures is often associated with delayed union. We have investigated whether union can be enhanced by using recombinant bone morphogenetic protein-7 (rhBMP-7). Osteoinduction with rhBMP-7 and bovine collagen was used in 20 patients with distal tibial fractures which had been treated by external fixation (BMP group). Healing of the fracture was compared with that of 20 matched patients in whom treatment was similar except that rhBMP-7 was not used. Significantly more fractures had healed by 16 (p = 0.039) and 20 weeks (p = 0.022) in the BMP group compared with the matched group. The mean time to union (p = 0.002), the duration of absence from work (p = 0.018) and the time for which external fixation was required (p = 0.037) were significantly shorter in the BMP group than in the matched group. Secondary intervention due to delayed healing was required in two patients in the BMP group and seven in the matched group. RhBMP-7 can enhance the union of distal tibial fractures treated by external fixation.
Dislocation of the shoulder may occur during
seizures in epileptics and other patients who have convulsions. Following
the initial injury, recurrent instability is common owing to a tendency
to develop large bony abnormalities of the humeral head and glenoid
and a susceptibility to further seizures. Assessment is difficult
and diagnosis may be missed, resulting in chronic locked dislocations
with protracted morbidity. Many patients have medical comorbidities,
and successful treatment requires a multidisciplinary approach addressing
the underlying seizure disorder in addition to the shoulder pathology.
The use of bony augmentation procedures may have improved the outcomes
after surgical intervention, but currently there is no evidence-based
consensus to guide treatment. This review outlines the epidemiology
and pathoanatomy of seizure-related instability, summarising the
currently-favoured options for treatment, and their results.
The treatment of substantial proximal femoral
bone loss in young patients with developmental dysplasia of the
hip (DDH) is challenging. We retrospectively analysed the outcome
of 28 patients (30 hips) with DDH who underwent revision total hip
replacement (THR) in the presence of a deficient proximal femur,
which was reconstructed with an allograft prosthetic composite.
The mean follow-up was 15 years (8.5 to 25.5). The mean number of
previous THRs was three (1 to 8). The mean age at primary THR and
at the index reconstruction was 41 years (18 to 61) and 58.1 years
(32 to 72), respectively. The indication for revision included mechanical
loosening in 24 hips, infection in three and peri-prosthetic fracture
in three. Six patients required removal and replacement of the allograft
prosthetic composite, five for mechanical loosening and one for
infection. The survivorship at ten, 15 and 20 years was 93% (95%
confidence interval (CI) 91 to 100), 75.5% (95% CI 60 to 95) and
75.5% (95% CI 60 to 95), respectively, with 25, eight, and four
patients at risk, respectively. Additionally, two junctional nonunions
between the allograft and host femur required bone grafting and
plating. An allograft prosthetic composite affords a good long-term outcome
in the management of proximal femoral bone loss in revision THR
in patients with DDH, while preserving distal host bone.