Carl Ekholm

Critical factors in cut-out complication after gamma nail treatment of proximal femoral fractures

BackgroundThe most common mechanical failure in the internal fixation of trochanteric hip fractures is the cut-out of the sliding screw through the femoral head. Several factors that influence this complication have been suggested, but there is no consensus as to the relative importance of each factor.The purpose of this study was to analyse the cut-out complication with respect to the following variables: patients’ age, fracture type, fracture reduction, implant positioning and implant design.Methods3066 consecutive patients were treated for trochanteric fractures with Gamma Nails between 1990 and 2002 at the Centre de Traumatologie et de l`Orthopedie (CTO), Strasbourg, France. Cut-out complications were identified by reviewing all available case notes and radiographs. Subsequently, the data were analysed by a single reviewer (AJB) with focus on the studied factors.ResultsSeventy-one cut-out complications were found (2.3%) of the 3066 trochanteric fractures. Cut-out failure associated with avascular head necrosis, pathologic fracture, deep infection or secondary to prior failure of other implants were excluded from the study (14 cases). The remaining 57 cases (1.85 %, median age 82.6, 79% females) were believed to have a biomechanical explanation for the cut-out failure. 41 patients had a basicervical or complex fracture type. A majority of cut-outs (43 hips, 75%) had a combination of the critical factors studied; non-anatomical reduction, non-optimal lag screw position and the characteristic fracture pattern found.ConclusionsThe primary cut-out rate of 1.85% was low compared with the literature. A typical cut-out complication in our study is represented by an unstable fracture involving the trochanteric and cervical regions or the combination of both, non-anatomical reduction and non-optimal screw position. Surgeons confronted with proximal femoral fractures should carefully scrutinize preoperative radiographs to assess the primary fracture geometry and fracture classification. To reduce the risk of a cut-out it is important to achieve both anatomical reduction and optimal lag screw position as these are the only two factors that can be controlled by the surgeon.

The Ilizarov external fixator - a useful alternative for the treatment of proximal tibial fractures A prospective observational study of 30 consecutive patients

BackgroundIn dislocated proximal tibial fractures, the most frequently used treatment is ORIF with screws and plates. Minimally-invasive techniques using external fixation are an alternative. The aim of this study was to analyse the clinical and radiological results using the Ilizarov technique in both uni- and bicondylar tibial fractures.MethodsThirty consecutive patients with isolated fractures of the proximal tibia were treated with the Ilizarov technique, 11 Schatzker I-IV with 2–3 rings and 19 Schatzker V-VI with 3–4 tibial rings and a femoral, hinged, two-ring extension. Unrestricted weight-bearing was allowed. Pre and post-operatively, conventional radiographs, computerized tomography scans, post-operative pain assessments and complications were evaluated. The knee function was evaluated with the EQ-5D, NHP and KOOS scores, as well as self-appraisal.ResultsAll the fractures healed. Twenty-five patients achieved a range of motion better than 10-100º. The type I-IV fractures had a shorter operating time and hospital stay, as well as better knee flexion, and the self-appraisal indicated that they tolerated the treatment better. Pin infections occurred in 4% of the pin sites, but only two patients required debridement. Two patients developed compartment syndrome and underwent fasciotomy. No patient complained of functional knee instability. Two patients underwent a total knee arthroplasty because of residual pain. The overall result was judged as satisfactory in twenty-seven patients.ConclusionsThe Ilizarov method produces a good clinical outcome and is a valuable treatment alternative in proximal tibial fractures of all types.

The Swedish fracture register: 103,000 fractures registered

BackgroundAlthough fractures consume large social and financial resources, little is known about their actual numbers, treatment methods or outcomes. The scarcity of data calls for a high-quality, population-based register. No previous registers have prospectively collected data and patient-reported outcome measures (PROMs) on fractures of all types. The Swedish Fracture Register was recently created to fill this gap in knowledge. Its purpose is to provide information on fractures of all types, whether treated by surgery or otherwise. The aim of this article is to describe how the register was developed and its current use.DescriptionThe Swedish Fracture Register was developed during a 4-year period, 2007–2010. Data collection started in 2011. The register currently collects data on all extremity, pelvic and spine fractures in adults who have been diagnosed or treated at the affiliated departments. Data entry is fully web based, including date, cause of injury, classification and treatment. It is performed by the attending physician. Patients fill out PROMs – EQ-5D-3L and the Short Musculoskeletal Function Assessment (SMFA) – relating to health status and level of functioning before the fracture and one year later. Surgeon-reported outcome measures are registered as reoperation rates. The Swedish Fracture Register is now functioning effectively and is used in clinical routine. From January 2011 to September 2015, more than 103,000 fractures have been entered at 26 Swedish orthopedic departments.ConclusionsThe Swedish Fracture Register is already a well-functioning, population-based fracture register that covers fractures of all types, regardless of treatment, and collects both surgeon- and patient-reported outcome measures. In the future the Swedish Fracture Register will be able to present both results of fracture treatment and valuable epidemiological data.

LH-induced inhibition of follicular androgen formation requires intact steroidogenesis

LH exerts a biphasic effect on rat pre-ovulatory follicular steroidogenesis: an initial (1-4h) overall stimulation followed by a later (4-6 h) occurring inhibition of androgen synthesis. Because exogenous steroids may inhibit androgen formation, we investigated whether the steroids produced initially in response to LH are involved in the late inhibition of androgen synthesis. Isolated pre-ovulatory rat follicles were incubated for 6 h with and without ovine LH and 1 of 3 inhibitors of steroidogenesis (aminoglutethimide, cyanoketone, Su 10603). Accumulation of androstenedione and testosterone in a subsequent 2-h incubation in the presence of exogenous 17-hydroxyprogesterone was measured. LH treatment alone caused inhibition of apparent 17,20-lyase activity. The inhibitors had no effect on basal 17,20-lyase activity but were able to prevent the LH-induced inhibition of this enzyme activity. The results suggest that the physiological decline in pre-ovulatory androgen formation may in part be mediated by local action of follicular steroids.

High reliability in classification of tibia fractures in the Swedish Fracture Register

INTRODUCTION The Swedish Fracture Register (SFR) was started in 2011 and registers fractures of all types, treated either surgically or non-surgically. Twenty-six orthopaedic departments in Sweden are affiliated and a total of 84,000 fractures have been registered. The physician who establishes the diagnosis of the fracture registers and classifies it according to the AO/OTA classification. The accuracy of the classification of fractures is important for the reliability of the data in the SFR. This study aimed to evaluate how accurate the classification of tibia fractures in the register is. METHODS Three experienced trauma surgeons (raters) were presented with the radiographs of 114 patients with tibia fractures randomly allocated from the SFR. The raters classified the fractures independently and blinded to clinical patient information in two classification sessions with a time interval of one month. The AO/OTA classification coded by the three expert raters (our predefined gold standard) was compared with the classifications in the SFR. Inter- and intra-observer agreement was evaluated. The degree of agreement was reported using the approach of Landis and Koch. RESULTS The accuracy of the SFR, defined as agreement between the SFR and the gold standard classification, was kappa=0.75 for the AO/OTA type and 0.56 for the AO/OTA group, corresponding to substantial and moderate agreement, respectively. Inter-observer agreement across the three expert raters was kappa=0.74 for the AO/OTA type and 0.53 for the AO/OTA group. Intra-observer agreement was kappa=0.74-0.79 for the AO/OTA type and 0.62-0.64 for the AO/OTA group. CONCLUSION This study shows that the accuracy of classification of tibia fractures in the SFR was substantial for the AO/OTA type (kappa=0.75) and moderate for the AO/OTA group (kappa=0.56) as defined by Landis and Koch. This degree of accuracy is similar to that in previous studies. We interpret this as meaning that the results of this study demonstrate the high reliability of the data in the SFR and enable the SFR to be used for further scientific analysis.

Three-dimensional bone-implant movements in trochanteric hip fractures: Precision and accuracy of radiostereometric analysis in a phantom model

The accuracy and precision of RSA were evaluated in the experimental study of screw cut‐out complication after fixation of trochanteric fractures. A plastic bone model of a two‐part trochanteric fracture was constructed with a Gamma nail implant incorporating RSA markers. The femoral head fragment was attached to a separate rotational table and the femoral shaft was mounted on the micrometer. Three main motions were simulated: Femoral head translation and rotation along the axis of the lag screw and fracture fragment translation along anatomical axes. Accuracy and precision were determined according to ISO 16,087 and ASTM standard F2385‐04. Translations along the lag screw axis were measured with a precision within  ±0.14 mm and an accuracy within ±0.03 mm. With simultaneous translations along all three anatomical axes, lowest precision was measured for the x‐axis (±0.29, 0.07 mm, respectively), but improved when analyzed as a vector (±0.08, 0.03 mm). The precision and accuracy of femoral head rotations were within 0.5° and 0.18°, respectively. The resolution of the RSA method tested in this model was high, though it varied depending on the type of analyzed motion. This information is valuable when selecting and interpreting outcome parameters evaluating implant migration and osteosynthesis stability in future clinical RSA studies.

Hemiarthroplasty for irreparable distal humeral fractures: medium-term follow-up of 42 patients

We report our experience of performing an elbow hemiarthroplasty in the treatment of comminuted distal humeral fractures in the elderly patients. A cohort of 42 patients (three men and 39 women, mean age 72; 56 to 84) were reviewed at a mean of 34.3 months (24 to 61) after surgery. Functional outcome was measured with the Mayo Elbow Performance Score (MEPS) and range of movement. The disabilities of the arm, shoulder and hand questionnaire (DASH) was used as a patient rated evaluation. Complications and ulnar nerve function were recorded. Plain radiographs were obtained to assess prosthetic loosening, olecranon wear and heterotopic bone formation. The mean extension deficit was 23.5° (0° to 60°) and mean flexion was 126.8° (90° to 145°) giving a mean arc of 105.5° (60° to 145°). The mean MEPS was 90 (50 to 100) and a mean DASH score of 20 (0 to 63). Four patients had additional surgery for limited range of movement and one for partial instability. One elbow was revised due to loosening, two patients had sensory ulnar nerve symptoms, and radiographic signs of mild olecranon wear was noted in five patients. Elbow hemiarthroplasty for comminuted intra-articular distal humeral fractures produces reliable medium-term results with functional outcome and complication rates, comparable with open reduction and internal fixation and total elbow arthroplasty.

ROLE OF CUMULUS CELLS IN OOCYTE MATURATION

Resumption of meiosis (oocyte maturation) is normally triggered by the preovulatory LH surge, and the first meiotic division is completed at the time of follicle rupture. The mature follicle has receptors for LH both in the theca and granulosa cells but no specific LH receptors have been demonstrated on the oocyte itself. Therefore, the triggering effect of LH on meiosis is likely to be mediated indirectly by an effect on the somatic cell types, probably the granulosa cells. We have studied the mechanism of LH action on meiosis with particular emphasis on the relation to the cumulus cells. In this review we will summarize some of our previous findings as well as report on some new results. We focus on studies where oocyte and cumulus maturation have been studied in relation to metabolic changes (1) of the whole isolated follicle and (2) of the isolated oocyte-cumulus complex.

Acute stimulatory effects of luteinizing hormone-releasing hormone (LHRH) and LHRH analogues on the preovulatory rat follicle

Publisher Summary This chapter discusses acute stimulatory effects of luteinizing hormone-releasing hormone (LHRH) and LHRH analogues on the preovulatory rat follicle. In a study described in the chapter, immature Sprague–Dawley rats, 26 days old, were treated with 10 IU PMSG. This treatment resulted in the ovulation of 12–18 ova early on the morning of day 29. Ovarian follicles or granulosa cells were isolated on the morning of day 28. The follicles were incubated in Krebs–Ringer bicarbonate buffer with glucose and 1% bovine serum albumin. Granulosa cells were cultured in Eagles minimal essential medium with Hepes and 10% fetal calf serum. For the in vivo experiments, the rats were hypophysectomized on the morning of day 28. It was found that mammalian oocytes remain arrested in the prophase stage of the first meiotic division until meiosis is resumed in the preovulatory follicle following the LH surge. Oocyte meiosis can also be initiated in vitro by the addition of gonadotrophin to isolated preovulatory rat follicles.

Trochanteric fracture-implant motion during healing – A radiostereometry (RSA) study

Cut-out complication remains a major unsolved problem in the treatment of trochanteric hip fractures. A better understanding of the three-dimensional fracture-implant motions is needed to enable further development of clinical strategies and countermeasures. The aim of this clinical study was to characterise and quantify three-dimensional motions between the implant and the bone and between the lag screw and nail of the Gamma nail. Radiostereometry Analysis (RSA) analysis was applied in 20 patients with trochanteric hip fractures treated with an intramedullary nail. The following three-dimensional motions were measured postoperatively, at 1 week, 3, 6 and 12 months: translations of the tip of the lag screw in the femoral head, motions of the lag screw in the nail, femoral head motions relative to the nail and nail movements in the femoral shaft. Cranial migration of the tip of the lag screw dominated over the other two translation components in the femoral head. In all fractures the lag screw slid laterally in the nail and the femoral head moved both laterally and inferiorly towards the nail. All femoral heads translated posteriorly relative to the nail, and rotations occurred in both directions with median values close to zero. The nail tended to retrovert in the femoral shaft. Adverse fracture-implant motions were detected in stable trochanteric hip fractures treated with intramedullary nails with high resolution. Therefore, RSA method can be used to evaluate new implant designs and clinical strategies, which aim to reduce cut-out complications. Future RSA studies should aim at more unstable fractures as these are more likely to fail with cut-out.