Outcome after total knee arthroplasty in haemophilic patients with stiff knees

INTRODUCTION

Advanced haemophilic arthropathy of the knee is associated with progressive joint stiffness. Results after total knee arthroplasty (TKA) in stiff knees are considered to be inferior compared to those with less restricted preoperative range of motion (ROM). There is only very limited data on the results of primary TKA in haemophilic patients with stiff knees.

AIM

The purpose of this retrospective study was to evaluate the clinical outcome after TKA performed in haemophilic patients with preoperative ROM of 50° or less.

METHODS

Twenty one patients (23 knees) undergoing TKA with stiff knees were retrospectively evaluated. Mean follow-up was 8.3 years (range, 2-25). Clinical assessment included ROM, degree of flexion contracture and complication rate. Functional evaluation and pain status were assessed using the Knee Society's Scoring System (KSS).

RESULTS

Range of motion improved from 26.7° preoperatively to 73.0° postoperatively. Flexion contracture decreased from 21.7° to 8.3°. KSS increased from 22.9 to 72.9 points. Evaluation of pain revealed a decrease from 8.4 points preoperatively to 2.1 points postoperatively. All these differences were statistically significant (P < 0.005). The complication rate was 8.7% including one late periprosthetic infection, and one aseptic implant loosening. Nine patients who required VY-quadricepsplasty for knee exposure developed a mean postoperative extensor lag of 7°.

CONCLUSION

Total knee arthroplasty in haemophilic patients presenting with stiff knees results in significant improvement of function and reduction in pain. Although the clinical outcome is inferior compared to nonstiff knees reported in the literature, joint replacement surgery can be successfully performed in this particular group of patients.

Interferon alpha 2 maintenance therapy may enable high rates of treatment discontinuation in chronic myeloid leukemia

A minority of chronic myeloid leukemia (CML) patients is capable of successfully discontinuing imatinib. Treatment modalities to increase this proportion are currently unknown. Here, we assessed the role of interferon alpha 2a (IFN) on therapy discontinuation in a previously reported cohort of 20 chronic phase CML patients who were treated upfront with IFN alpha plus imatinib followed by IFN monotherapy to maintain cytogenetic or molecular remission (MR) after imatinib discontinuation. After a median follow-up of 7.9 years (range, 5.2-12.2), relapse-free survival was 73% (8/11 patients) and 84% (5/6 patients) for patients who discontinued imatinib in major MR (MMR) and MR4/MR4.5, respectively. Ten patients discontinued IFN after a median of 4.5 years (range, 0.24-9.3). After a median of 2.8 years (range, 0.7-5.1), nine of them remain in ongoing treatment-free remission with MR5 (n=6) and MR4.5 (n=3). The four patients who still administer IFN are in stable MR5, MR4.5, MR4, and MMR, respectively. In conclusion, an IFN/imatinib induction treatment followed by a temporary IFN maintenance therapy may enable a high rate of treatment discontinuation in CML patients in at least MMR when stopping imatinib.

Dual glutathione-S-transferase-θ1 and -μ1 gene deletions determine imatinib failure in chronic myeloid leukemia

Approximately 40% of patients with chronic myeloid leukemia (CML) receiving imatinib fail treatment. There is an increased risk of CML in subjects with (i) deletions of genes encoding glutathione-S-transferase (GST)-θ1 (GSTT1) and -μ1, (GSTM1) and (ii) the GST-π1 (GSTP1) single-nucleotide polymorphism (SNP) Ile105Val (GSTP1*B; rs1695); however, their effects on imatinib treatment outcome are not known. Here, we assess the role of these GSTs in relation to imatinib treatment outcome in 193 CML patients. Deletion of GSTT1 alone, or in combination with deletion of the GSTM1 gene, significantly increased the likelihood of imatinib failure (P = 0.021 and P < 0.001, respectively). The GSTP1*B SNP was not associated with time to imatinib failure. Losses of the GSTT1 and GSTM1 genes are therefore important determinants of imatinib failure in CML. Screening for GSTT1 and GSTM1 gene deletions during diagnosis may identify patients who may be better treated using an alternative therapy.

[Evaluation of radiation exposure of personnel in an orthopaedic and trauma operation theatre using the new real-time dosimetry system "dose aware"]

AIM

There is a positive correlation between operation time and staff exposure to radiation during intraoperative use of C-arm fluoroscopy. Due to harmful effects of exposure to long-term low-dose radiation for both the patient and the operating team it should be kept to a minimum. AIM of this study was to evaluate a novel dosimeter system called Dose Aware® (DA) enabling radiation exposure feedback of the personal in an orthopaedic and trauma operation theatre in real-time.

METHOD

Within a prospective study over a period of four month, DA was applied by the operation team during 104 orthopaedic and trauma operations in which the C-arm fluoroscope was used in 2D-mode. During ten operation techniques, radiation exposure of the surgeon, the first assistant, the theatre nurse and the anaesthesiologist was evaluated.

RESULTS

Seventy-three operations were analysed. The surgeon achieved the highest radiation exposure during dorsolumbar spinal osteosynthesis, kyphoplasty and screw fixation of sacral fractures. The first assistant received a higher radiation exposure compared to the surgeon during plate osteosynthesis of distal radius fractures (157 %), intramedullary nailing of pertrochanteric fractures (143 %) and dorsolumbar spinal osteosynthesis (240 %). During external fixation of ankle fractures (68 %) and screw fixation of sacral fractures (66 %) radiation exposure of the theatre nurse exceeded 50 % of the surgeon's radiation exposure. During plate osteosynthesis of distal radius fractures (157 %) and intramedullary splinting of clavicular fractures (115 %), the anaesthesiologist received a higher radiation exposure than the surgeon.

CONCLUSION

The novel dosimeter system DA provides real-time radiation exposure feedback of the personnel in an orthopaedic and trauma operation theatre for the first time. Data of this study demonstrate that radiation exposure of the personnel depends on the operation type. The first assistant, the theatre nurse and the anaesthesiologist might be exposed to higher radiation doses than the surgeon. DA might help to increase awareness concerning irradiation in an orthopaedic and trauma operation theatre and might enhance staff compliance in using radiation protection techniques.

A certified plasmid reference material for the standardisation of BCR-ABL1 mRNA quantification by real-time quantitative PCR

Serial quantification of BCR–ABL1 mRNA is an important therapeutic indicator in chronic myeloid leukaemia, but there is a substantial variation in results reported by different laboratories. To improve comparability, an internationally accepted plasmid certified reference material (CRM) was developed according to ISO Guide 34:2009. Fragments of BCR–ABL1 (e14a2 mRNA fusion), BCR and GUSB transcripts were amplified and cloned into pUC18 to yield plasmid pIRMM0099. Six different linearised plasmid solutions were produced with the following copy number concentrations, assigned by digital PCR, and expanded uncertainties: 1.08±0.13 × 10⁶, 1.08±0.11 × 10⁵, 1.03±0.10 × 10⁴, 1.02±0.09 × 10³, 1.04±0.10 × 10² and 10.0±1.5 copies/μl. The certification of the material for the number of specific DNA fragments per plasmid, copy number concentration of the plasmid solutions and the assessment of inter-unit heterogeneity and stability were performed according to ISO Guide 35:2006. Two suitability studies performed by 63 BCR–ABL1 testing laboratories demonstrated that this set of 6 plasmid CRMs can help to standardise a number of measured transcripts of e14a2 BCR–ABL1 and three control genes (ABL1, BCR and GUSB). The set of six plasmid CRMs is distributed worldwide by the Institute for Reference Materials and Measurements (Belgium) and its authorised distributors (https://ec.europa.eu/jrc/en/reference-materials/catalogue/; CRM code ERM-AD623a-f).

[Thromboembolic complications 6 months after plate osteosynthesis of a mid-clavicular fracture]

A 32-year-old patient suffered from progredient intermittent claudication of the left arm 6 months after plate fixation of a midshaft clavicular fracture (OTA classification type A). The radiological analysis revealed a subacute stenosis of the left subclavian artery, caused by a granuloma at the tip of a protruding screw, which triggered recurrent emboli and symptoms. Reperfusion was achieved by catheter embolectomy and complete removal of the plate. The case shows that, when performing plate osteosynthesis of clavicular fractures, special consideration has to be given to the length and protrusion of the applied screws. Due to the anatomic proximity not only acute, but also subsequent irritation of the subclavian vessels is possible.

MDR1 expression predicts outcome of Ph+ chronic phase CML patients on second-line nilotinib therapy after imatinib failure

In the face of competing tyrosine kinase inhibitors (TKIs), identification of chronic myeloid leukemia (CML) patients expecting favorable response to second-line treatment is warranted. At the time of imatinib resistance, the investigation of multidrug-resistance protein 1 (MDR1) and BCR-ABL yielded the following results: (i) Patients with high MDR1 transcript levels showed superior response at 48 months as compared with low-level MDR1 patients: major molecular response (MMR) in 41% vs 16% (P=0.014), complete cytogenetic response (CCyR) in 58% vs 39% (P=0.044), and progression-free survival (PFS) in 67% vs 46% (P=0.032). (ii) Patients with BCR-ABL(IS) <28% achieved higher MMR rates (48% vs 21%, P=0.009). (iii) PFS at 48 months was associated with in vitro resistance of BCR-ABL kinase domain mutations: 63% (no mutation) vs 61% (sensitive, intermediately sensitive or unknown IC50 (median inhibitory concentration)) vs 23% (resistant, P=0.01). (iv) Single-nucleotide polymorphisms (SNPs) at positions 1236 and 2677 were associated with higher MDR1 expression in comparison to wild type. (v) Nilotinib was able to impede proliferation of MDR1-overexpressing imatinib-resistant cells. High MDR1 gene expression might identify patients whose mode of imatinib resistance is essentially determined by increased efflux activity of MDR1 and therefore can be overcome by second-line nilotinib treatment.

A phase 2 trial of ponatinib in Philadelphia chromosome-positive leukemias

BACKGROUND

Ponatinib is a potent oral tyrosine kinase inhibitor of unmutated and mutated BCR-ABL, including BCR-ABL with the tyrosine kinase inhibitor-refractory threonine-to-isoleucine mutation at position 315 (T315I). We conducted a phase 2 trial of ponatinib in patients with chronic myeloid leukemia (CML) or Philadelphia chromosome-positive acute lymphoblastic leukemia (Ph-positive ALL).

METHODS

We enrolled 449 heavily pretreated patients who had CML or Ph-positive ALL with resistance to or unacceptable side effects from dasatinib or nilotinib or who had the BCR-ABL T315I mutation. Ponatinib was administered at an initial dose of 45 mg once daily. The median follow-up was 15 months.

RESULTS

Among 267 patients with chronic-phase CML, 56% had a major cytogenetic response (51% of patients with resistance to or unacceptable side effects from dasatinib or nilotinib and 70% of patients with the T315I mutation), 46% had a complete cytogenetic response (40% and 66% in the two subgroups, respectively), and 34% had a major molecular response (27% and 56% in the two subgroups, respectively). Responses were observed regardless of the baseline BCR-ABL kinase domain mutation status and were durable; the estimated rate of a sustained major cytogenetic response of at least 12 months was 91%. No single BCR-ABL mutation conferring resistance to ponatinib was detected. Among 83 patients with accelerated-phase CML, 55% had a major hematologic response and 39% had a major cytogenetic response. Among 62 patients with blast-phase CML, 31% had a major hematologic response and 23% had a major cytogenetic response. Among 32 patients with Ph-positive ALL, 41% had a major hematologic response and 47% had a major cytogenetic response. Common adverse events were thrombocytopenia (in 37% of patients), rash (in 34%), dry skin (in 32%), and abdominal pain (in 22%). Serious arterial thrombotic events were observed in 9% of patients; these events were considered to be treatment-related in 3%. A total of 12% of patients discontinued treatment because of an adverse event.

CONCLUSIONS

Ponatinib had significant antileukemic activity across categories of disease stage and mutation status. (Funded by Ariad Pharmaceuticals and others; PACE ClinicalTrials.gov number, NCT01207440 .).

[Elastic titanium nails for minimally invasive intramedullary splinting of metacarpal fractures]

AIM

The goal in treatment of metacarpal fractures is to restore the normal function of the hand. Although a majority of these fractures can be treated non-operatively, surgery is recommended for displaced fractures and in case of a patient wish for primary stability for practise. A poor clinical outcome is described for metacarpal shortening of more than 5 millimeters and for rotational deformity. Whereas plate osteosynthesis may lead to soft tissue irritation involving tendon adhesions and scar formation, we have used the elastic stable intramedullary nailing [ESIN] technique using titanium elastic nails (TEN) for intramedullary splinting of short metacarpal shaft and neck fractures.

METHOD

Within 5 years, ESIN was performed in 95 patients. The operative technique was evaluated retrospectively concerning its functional results and complications.

RESULTS

Sixty-three patients were analysed after an average follow-up of 14.0 ± 5.2 weeks. The mean DASH-Score was 2.3 ± 3.9 points. We saw one implant out-of-position and three cases of skin irritation affording TEN shortening. Two superficial wound infections were treated conservatively. Pseudarthrosis and nail breakage were not observed. After TEN removal 9 ± 2.4 weeks post implantationem no refracture occurred.

CONCLUSION

Minimally invasive intramedullary stabilisation of short metacarpal shaft and neck fractures with a TEN is a safe surgical technique and achieves primary stability for practise. It reliably leads to fracture healing and produces excellent functional results.

[Basic principles of surgical treatment of bone metastases]

Due to an increased life expectancy and improved oncological treatment, the necessity for surgical treatment of bone metastases has increased as well. Ideally, therapy should concentrate on the improvement of the patient's quality of life while preferably being interdisciplinary. The type and extent of surgical therapy depend on the prognosis, tumor entity, localization of the tumor as well as on the patient's general condition. The main aims of surgical treatment is to reduce pain and preserve or restore function and mobility. After the contribution on spinal metastases in the last volume, this article focusses on metastases of the extremities and the pelvis. Pathologic fractures with an unclear oncological situation should be examined thoroughly before any surgical treatment is performed. In case of doubt, a biopsy should be performed. Depending on the individual prognosis, possible options for extremity surgery are (compound) osteosynthesis and implantation of a tumor endoprosthesis. The latter should be preferred for patients with a favorable prognosis and long life expectancy. To avoid revision surgery, the selected implant should outlast the patient's remaining life expectancy.

Early molecular and cytogenetic response is predictive for long-term progression-free and overall survival in chronic myeloid leukemia (CML)

In the face of competing first-line treatment options for CML, early prediction of prognosis on imatinib is desirable to assure favorable survival or otherwise consider the use of a second-generation tyrosine kinase inhibitor (TKI). A total of 1303 newly diagnosed imatinib-treated patients (pts) were investigated to correlate molecular and cytogenetic response at 3 and 6 months with progression-free and overall survival (PFS, OS). The persistence of BCR-ABL transcript levels >10% according to the international scale (BCR-ABL(IS)) at 3 months separated a high-risk group (28% of pts; 5-year OS: 87%) from a group with >1-10% BCR-ABL(IS) (41% of pts; 5-year OS: 94%; P=0.012) and from a group with ≤1% BCR-ABL(IS) (31% of pts; 5-year OS: 97%; P=0.004). Cytogenetics identified high-risk pts by >35% Philadelphia chromosome-positive metaphases (Ph+, 27% of pts; 5-year OS: 87%) compared with ≤35% Ph+ (73% of pts; 5-year OS: 95%; P=0.036). At 6 months, >1% BCR-ABL(IS) (37% of pts; 5-year OS: 89%) was associated with inferior survival compared with ≤1% (63% of pts; 5-year OS: 97%; P<0.001) and correspondingly >0% Ph+ (34% of pts; 5-year OS: 91%) compared with 0% Ph+ (66% of pts; 5-year OS: 97%; P=0.015). Treatment optimization is recommended for pts missing these landmarks.

[Replacement of the comminuted radial head fracture by a bipolar radial head prosthesis]

OBJECTIVE

Radial head arthroplasty as a treatment of non-reconstructable, comminuted fractures of the radial head in order to achieve elbow stability and to prevent secondary complications, such as valgus elbow instability and radius proximalization.

INDICATIONS

In acute trauma, a radial head fracture not suitable for internal fixation without (Mason grade III) and with (Mason grade IV) concomitant destabilizing injury, Essex-Lopresti injury, sequelae following radial head resection (e.g., elbow instability or wrist pain), failed reconstruction of the radial head, and tumor-associated radial head or neck resection.

CONTRAINDICATIONS

General medical contraindications for surgical intervention, cobalt-chromium allergy, and osteoporosis of the proximal radius.

SURGICAL TECHNIQUE

In supine position, a lateral or posterolateral approach at the elbow was used. The annular ligament was exposed and the radial neck identified just above the bicipital tuberosity. In pronation of the forearm in order to protect the radial nerve, the medullary canal was prepared using rasps. The size of the implant was determined using trial stems. A distance of 0.5 mm between the head of the prosthesis and the capitulum humeri was recommended. After using a small bone plug, the prosthesis was cemented with respect to the anatomical radial curvature. After reconstruction of the annular ligament, the stability of the elbow was verified. In case of instability, the medial collateral ligament was reconstructed and afterwards the wound closed.

POSTOPERATIVE MANAGEMENT

Early mobilization begins the day after surgery. In case of additional injuries, the elbow was supported by an above-elbow cast for 3-4 weeks. To prevent heterotopic ossification, nonsteroidal antiinflammatory drugs were used for up to 4 weeks with gastric protection.

RESULTS

A total of 13 patients with 15 radial head prosthesis were analyzed at a mean follow-up of 29.5±20.8 months. In all patients, the elbow was stable. Subjectively, good and excellent results were found with one exception. Compared to the pretrauma status, the subjective rate was 78±12%. Based on the Radin and Riseborough score, 6 of the results were good and 9 were fair. According to the Broberg and Morrey score, 1 result was very good, 8 were good, and 6 were fair. The mean DASH score was 9.9±9.7 points. Two temporary nerve lesions were observed. Five patients were diagnosed with heterotopic ossification stage I, while 2 patients were classified with stage II on the Brooker scale.

Evaluation of a new computer-assisted surgical planning and navigation system based on two-dimensional fluoroscopy for insertion of a proximal femoral nail: an experimental study

Pertrochanteric femoral fractures are common and intramedullary nailing is an accepted method for their surgical treatment. Accurate placement of the implant is essential to ensure fixation. The conventional technique can require multiple guide wire passes, and relies heavily on fluoroscopy. A computer-assisted planning and navigation system based on two-dimensional fluoroscopy for guide wire placement in the femoral neck has been developed, in order to perform intramedullary pertrochanteric fracture fixation using the proximal femoral nail (PFNA). The planning process was supported by a 'zero-dose C-arm navigation' system. The PFNA was inserted into 12, intact, femoral sawbones guided by the computer-based navigation, and into 12, intact, femoral sawbones using a conventional fluoroscopic-assisted technique. Guide wire and subsequent blade placement in the femoral neck was evaluated. The computer-assisted technique achieved a significant decrease in the number of required fluoroscopic images and in the number of guide wire passes. The obtained average blade placement accuracy in the femoral neck was equivalent to the conventional technique. The operation time was significantly longer in the navigation-assisted group. The addition of computer-assisted planning and surgical guidance to the intramedullary nailing of pertrochanteric femoral fractures offers a number of clinical benefits based on the results of this sawbone study. Further studies including fractured sawbones and cadaver models with extension of the navigation process to all steps of PFNA introduction and with the goal of reducing operation time are indispensable before integration of this navigation system into clinical practice.

Evaluation of a fluoroscopy-based navigation system enabling a virtual radiation-free preview of X-ray images for placement of cannulated hip screws. A cadaver study

Accurate placement of cannulated screws is essential to ensure fixation of medial femoral neck fractures. The conventional technique may require multiple guide wire passes, and relies heavily on fluoroscopy. A computer-assisted planning and navigation system based on 2D fluoroscopy for guide wire placement in the femoral neck has been developed to improve screw placement. The planning process was supported by a tool that enables a virtual radiation-free preview of X-ray images. This is called "zero-dose C-arm navigation". For the evaluation of the system, six formalin-fixed cadaveric full-body specimens (12 femurs) were used. The evaluation demonstrated the feasibility of fluoroscopically navigated guide wire and implant placement. Use of the novel system resulted in a significant reduction in the number of fluoroscopic images and drilling attempts while achieving optimized accuracy by attaining better screw parallelism and enlarged neck-width coverage. Operation time was significantly longer in the navigation assisted group. The system has yielded promising initial results; however, additional studies using fractured bone models and with extension of the navigation process to track two bone fragments must be performed before integration of this navigation system into the clinical workflow is possible, and these studies should focus on reducing the operation time.

[Evaluation of a 2D fluoroscopy-based navigation system for insertion of the dynamic hip screw (DHS): an experimental study]

PURPOSE

Dynamic hip screw (DHS) insertion for the fixation of lateral femoral neck fractures is an accepted surgical treatment method. A computer-assisted planning and navigation system based on 2D fluoroscopy has been developed for guidewire insertion in order to perform screw placement. The image acquisition process was supported by a radiation-saving procedure called "zero-dose C-arm navigation". The aim of this study was to evaluate this new system.

MATERIALS AND METHODS

In the context of a sawbone study, we inserted dynamic hip screws. The procedure was performed under navigation control and in the conventional technique in 12 sawbones. Both procedures were performed in an open and closed technique.

RESULTS

The computer-assisted technique significantly reduced the number of intraoperative fluoroscopic images (open technique: -8.1 ± 0.5; p < 0.001 - closed technique: -12.3 ± 3.7; p < 0.001) and the number of guidewire passes (open technique: -1.3 ± 1.2; p < 0.05 - closed technique: -1.5 ± 1.2; p < 0,05). There was no difference with respect to precision in both groups. The operation time was significantly longer in the navigation-assisted groups (open technique: + 14.6 ± 5.4 min; p < 0.001 - closed technique: + 13 ± 3 min; p < 0.001).

CONCLUSION

The addition of computer-assisted planning and surgical guidance supported by "zero-dose C-arm navigation" may be useful for the fixation of lateral femoral neck fractures by the DHS as it reduces the amount of fluoroscopic images and requires fewer drill tracks. Further studies with the goal of reducing the operation time are necessary.

[Evaluation of a 2D fluoroscopy-based navigation system for insertion of femoral neck screws. An experimental study]

INTRODUCTION

The aim of this study was the evaluation of a new computer-assisted planning and navigation system based on 2D-fluoroscopy for guidewire insertion in order to perform cannulated screw placement into the femoral neck. The image acquisition process was supported by a radiation-saving procedure called Zero-dose C-arm navigation.

MATERIAL AND METHODS

In the context of a sawbone study, we performed insertion of 3 cannulated screws positioned under navigation control as well as using the conventional technique in 12 sawbones. Both procedures were performed using open and closed techniques.

RESULTS

The computer-assisted technique significantly reduced the amount of intraoperative fluoroscopic images (open technique: -14±3 images, closed technique: -29.4±6 images). Drilling attempts were reduced in the computer-assisted groups (open technique: -1.2±1 attempts, closed technique: -1.7±1.5 attempts) and the femoral neck area covered by the screws was greater in the navigation-assisted groups (open technique: +32.1±16.3 mm(2), closed technique: +32.6±14.9 mm(2)), There was no difference concerning parallelism of the screws or perforation of femoral neck or head. The operation time was significantly longer in the navigation-assisted groups (open technique: +24.2±2.1 min, closed technique: +22.8±5.8 min).

CONCLUSION

The addition of computer-assisted planning and surgical guidance supported by Zero-dose C-arm navigation can be useful for the fixation of medial femoral neck fractures with cannulated screws. Further studies with the goal of reducing the operation time are indispensable before integrating this navigation system into the clinical workflow.

[Clinical results after replacement of comminuted radial head fractures (Mason III and IV) by the bipolar radial head prosthesis of Judet]

AIM

Long-term results after resection of comminuted fractures of the radial head (Mason III and IV) may lead to valgus elbow instability, radius proximalisation and rotatory instability. Radial head replacement has been used to prevent and treat these complications. The aim of this study was to define the value of the bipolar radial head prosthesis of Judet for treating comminuted fractures of the radial head.

METHOD

Over a 5-year period, 14 radial head prosthesis were implanted in 12 patients. Retrospectively, we studied the clinical and radiological results.

RESULTS

Eleven patients with thirteen implants were analysed at a mean follow-up of 33.4 +/- 20.4 months. In all patients, the elbow was stable. Subjectively, we found good and excellent results with one exception. Compared to the pre-trauma status, the subjective rate was 78 +/- 12 %. According to the score of Radin and Riseborough, five of the results were found to be good and eight to be fair. According to the Broberg and Morrey score, one result was found to be very good, seven to be good and five to be fair. The mean DASH score was 10.2 +/- 10.1 points. Two temporary nerve lesions were observed.

CONCLUSION

In comminuted fractures of the radial head (Mason III and IV), bipolar radial head replacement with the Judet prosthesis leads subjectively to very good and good and functionally to good and fair results on the medium-term view. Joint stability is achieved and secondary complications like valgus elbow deformity and proximal radial migration are prevented. Patients must be informed about the possibility of temporary nerve lesions, heterotopic ossification causing limitation of motion and the lack of long-term results.

[Parkinson's disease influences the perioperative risk profile in trauma patients]

AIM

Parkinson's disease (PD) is one of the most common degenerative diseases of the central nervous system affecting elderly patients with increasing demographic prevalence. The aim of this study was to define the perioperative risk profile in trauma patients suffering from Parkinson's disease in order to improve treatment options in these patients.

METHOD

Over a period of 13 years, 16 patients suffering from Parkinson's disease treated in the department of trauma surgery were retrospectively compared using matched-pair analysis with 16 controls not affected by PD. Both groups of patients were assessed regarding morbidity, length of treatment and rehabilitation.

RESULTS

Trauma patients suffering from Parkinson's disease showed an increase in morbidity risk. Postoperative falls occurred significantly, infections of the urinary tract and pneumonia tendentiously more often in PD patients. Postoperative stay and length of treatment were significantly longer in patients with PD. These patients also tended to stay longer preoperatively and remained longer in intensive care. PD patients required on-ward rehabilitation significantly more often.

CONCLUSION

Concomitant Parkinson's disease is a significant factor of perioperative morbidity in trauma patients. Perioperative morbidity in PD patients may be influenced by early diagnostic and therapeutic measures.

[Elastic titanium nails in minimally invasive osteosynthesis for mid-clavicular fractures]

BACKGROUND

In up to 31% of cases, conservative treatment of mid-clavicular fractures leads to unsatisfactory results. The aim of this study was to define the value of minimally invasive elastic stable intramedullary nailing (ESIN) of mid-clavicular fractures with titanium elastic nails.

MATERIAL AND METHODS

Within 5 years, ESIN was performed in 45 patients. We studied the functional results and complications.

RESULTS

Retrospectively we analysed the results of all patients at a mean follow-up of 24.7+/-2.4 months. Iatrogenic perforation of the lateral cortex occurred twice and medial migration in eight patients. Superficial skin infection developed in one. Nail breakage after fracture healing was observed twice. Twelve patients sustained clavicular shortening of > or =5 mm in relation to the intact contralateral side. After 6 months the mean constant score was 94.3+/-2 points, and the mean DASH score was 5.4+/-2.2 points.

CONCLUSION

Intramedullary stabilisation of mid-clavicular fractures with titanium elastic nails is a minimally invasive technique with good functional results. Patients must be informed about the possibility of open reduction in about half of the cases as well as shoulder asymmetry, migration of the nail, and iatrogenic nerve and vessel injury.

Recurrent finding of the FIP1L1-PDGFRA fusion gene in eosinophilia-associated acute myeloid leukemia and lymphoblastic T-cell lymphoma

The FIP1L1-PDGFRA fusion gene has been described in patients with eosinophilia-associated myeloproliferative disorders (Eos-MPD). Here, we report on seven FIP1L1-PDGFRA-positive patients who presented with acute myeloid leukemia (AML, n=5) or lymphoblastic T-cell non-Hodgkin-lymphoma (n=2) in conjunction with AML or Eos-MPD. All patients were male, the median age was 58 years (range, 40-66). AML patients were negative for common mutations of FLT3, NRAS, NPM1, KIT, MLL and JAK2; one patient revealed a splice mutation of RUNX1 exon 7. Patients were treated with imatinib (100 mg, n=5; 400 mg, n=2) either as monotherapy (n=2), as maintenance treatment after intensive chemotherapy (n=3) or in overt relapse 43 and 72 months, respectively, after primary diagnosis and treatment of FIP1L1-PDGFRA-positive disease (n=2). All patients are alive, disease-free and in complete hematologic and complete molecular remission after a median time of 20 months (range, 9-36) on imatinib. The median time to achievement of complete molecular remission was 6 months (range, 1-14). We conclude that all eosinophilia-associated hematological malignancies should be screened for the presence of the FIP1L1-PDGFRA fusion gene as they are excellent candidates for treatment with tyrosine kinase inhibitors even if they present with an aggressive phenotype such as AML.

Gene expression signature of primary imatinib-resistant chronic myeloid leukemia patients

Although the selective tyrosine kinase inhibitor imatinib is successfully used in the treatment of chronic myeloid leukemia (CML), inherent mechanisms confer primary resistance to leukemic patients. In order to search for potentially useful genes in predicting cytogenetic response, a retrospective gene expression study was performed. Leukocyte RNA isolated before imatinib from interferon-alpha-pretreated chronic phase CML patients (n=34) with or without major cytogenetic remission (< or =35% Philadelphia (Ph)+ metaphases) during the first year of treatment was comparatively analyzed using Affymetrix U133A chips. Using support vector machines for gene classification, an outcome-specific gene expression signature consisting of 128 genes was identified. Comparative expression data of specific genes point to changes in apoptosis (e.g. casp9, tumor necrosis factor receptor-associated protein 1, hras), DNA repair (msh3, ddb2), oxidative stress protection (glutathione synthetase, paraoxonase 2, vanin 1) and centrosomes (inhibitor of differentiation-1) within primary resistant patients. Independent statistical approaches and quantitative real-time reverse transcriptase-polymerase chain reaction studies support the clinical relevance of gene profiling. In conclusion, this study establishes a candidate predictor of imatinib resistance in interferon-alpha-pretreated CML patients to be subjected to future investigation in a larger independent patient cohort. The resulting expression signature point to involvement of BCR-ABL-independent mechanisms of resistance.