Outcome of undisplaced and moderately displaced femoral neck fractures

Background The optimal treatment for femoral neck fracture is a matter of controversy. We compared the outcome of displaced fractures with good healing potential (moderately displaced fractures) to the outcome of undisplaced fractures treated by internal fixation with 2 parallel screws.

Methods In a consecutive series of hip fracture patients, the rates of reoperation and mortality for 225 undisplaced fractures were compared to those for 241 moderately displaced fractures. The patients were followed for 1-6 years.

Results The total rate of reoperation was 19% (9% because of healing complications) for the undisplaced fractures and 33% (20% because of healing complications) for the moderately displaced fractures. Fracture displacement was the main predictor of reoperation. There was no difference in mortality between the groups, and patient-related background parameters (rather than fracture displacement) were the main predictors of mortality.

Interpretation Undisplaced fractures should be treated by internal fixation. The best treatment for moderately displaced fractures remains to be determined.     

Decreasing incidence of hip fracture in the Funen County, Denmark

Background Hip fracture incidence rates are high, and increase with increasing age. Previous studies have predicted a continued increase in both crude and age-standardized rates.

Method We estimated incidence rates, based on a complete and validated register containing verified and individually sequenced hip fractures from 1996-2003, for a population of 500,000 people in Funen County, Denmark.

Results The verified number of the first hip fractures was 6,676, with 520 subsequent fractures. Between 1996 and 2003, the incidence rate of first hip fracture fell by 2.4% per year for males (p = 0.02) and by 1.8% per year for females (p = 0.004). The highest decrease of 3.4% per year (p = 0.02) was seen in 80-84-year-old women.

Interpretation The incidence rate of the first hip fracture has fallen in both sexes. In most age groups, the actual number of fractures has also decreased. The findings emphasize the need for valid projection studies which should include both demographic projections and modeling of the effects of different levels of prevention.     

Elastic stable intramedullary nailing of midclavicular fractures in adults: 32 patients followed for 1-5 years

Background Osteosynthesis of clavicular fractures is sometimes indicated. Since plate fixation may lead to complications, we have used elastic stable intramedullary nailing and report our experience of midclavicular fractures in 32 adults.

Patients and methods From 2000 to 2005, we treated 32 adults (26 men), median age 40 (19-66) years, by intramedullary nailing with a titanium elastic nail (TEN). All patients were re-examined after median 27 (12-59) months.

Results Nonunion was not observed. 20 clavicles healed without shortening. 12 clavicles healed with shortening of more than 5 mm. Migration of the TEN in 8 patients required secondary shortening of the nail in 5 of them. Nail breakage after fracture healing was observed twice. The nails were removed in 29 patients after a median of 6 (1.3-15) months postoperatively. No patient sustained a re-fracture after TEN removal. The mean Constant score was 95 (SD 1.9) points and the mean DASH score was 5 (SD 2.3) points.

Interpretation Intramedullary stabilization of midclavicular fractures with a titanium elastic nail is a minimally invasive technique with good cosmetic and functional results. Intramedullary fixation can be seen as an alternative to plate fixation and nonoperative treatment.     

The Polarus intramedullary nail for proximal humeral fractures: outcome in 28 patients followed for 1 year

Background One of the new treatment options for proximal humeral fractures is the minimally invasive intramedullary nail. In this study, we reviewed the early clinical results after 1 year.

Patients and methods 35 patients with proximal humeral fractures were treated using the Polarus nail. In 14 cases the initial treatment was operative; the other 21 patients were initially treated nonoperatively. 19 patients had a 2-part fracture, 5 had a 3-part fracture and 2 had a 4-part fracture. In 9 patients the fracture extended metaphyseally. The functional outcome was assessed by the Constant score.

Results 28 patients were available for 1-year followup. 17 patients showed excellent functional outcome (with an average Constant score of 81%). 6 patients required revision surgery, 1 because of nonunion and 1 because of an avascular necrosis. 4 others were reoperated because of inadequate position of the osteosynthesis or migration of the screws.

Interpretation The Polarus nail is of value for (displaced) 2-, 3-, and even 4-part proximal humeral fractures and enables early postoperative mobilization with a limited amount of pain.     

Women with low-energy fracture should be investigated for osteoporosis

Introduction Treatment of osteoporosis is becoming more effective, but methods to identify patients who are most suitable for investigation and treatment are still being debated. Should any type of fracture have higher priority for investigation of osteoporosis than any other? Is the number of previous fractures useful information?

Material and methods We investigated 303 consecutive women patients between 55 and 75 years of age who had a newly diagnosed low-energy fracture. They answered a questionnaire on previous fractures which also dealt with risk factors. Bone mineral density (BMD) was measured at the hip, lumbar spine, and forearm.

Results The distribution of fracture location was: distal forearm 56%, proximal humerus 12%, vertebra 18%, and hip 13%, all with similar age. Half of the subjects had had at least one previous fracture before the index fracture, 19% had had two previous fractures, and 6% had had three or more previous fractures. Patients with vertebral or hip fracture had lower BMD and had had more previous fractures than patients with forearm or humerus fractures. There was an inverse correlation between number of fractures and BMD. Osteoporosis was present in one-third of patients with forearm fracture, in one-half of those with hip or humerus fracture, and in two-thirds of those with vertebral fracture.

Interpretation Vertebral fractures were the strongest marker of low BMD and forearm fractures the weakest. The number of previous fractures is helpful information for finding the most osteoporotic patient in terms of severity. Investigation of osteoporosis therefore seems warranted in every woman between the ages of 55 and 75 with a recent low-energy fracture, with highest priority being given to those with vertebral, hip, or multiple fractures.     

Mice expressing a constitutively active PTH/PTHrP receptor in osteoblasts show reduced callus size but normal callus morphology during fracture healing

Background The parathyroid hormone-/parathyroid hormone-related protein (PTH/PTHrP) receptor plays a crucial role in endochondral bone formation and possibly also in fracture healing. Patients with Jansen's metaphysial chondrodysplasia (JMC) have a gain-of-function mutation in the PTH/PTHrP receptor. Transgenic mice expressing JMC PTH/PTHrP receptor mutants in osteoblasts are characterized by increased trabecular bone formation and reduced osteoblastic activity at periosteal sites. We have analyzed the bone phenotype and studied the fracture healing process in this model.

Methods We performed bone density analysis of tibiae from 17-week-old transgenic mice and controls. Also, tibial fractures were produced in 14-week-old mice. Fracture healing was examined by radiographic and histological analysis.

Results Transgenic mice had a lower total bone mineral content (BMC), by a factor of one-third. The changes were bone compartment-specific with an increase in trabecular bone volume and a decrease in cortical thickness. The calluses in the transgenic mice were smaller, with a reduction in BMC and mean crosssectional area by a factor of one-half. Despite the smaller size, however, the morphology and progression through the healing process were similar in both transgenic and wild-type littermates.

Interpretation We conclude that the constitutively active PTH/PTHrP receptor has compartment-specific effects on bone formation when expressed in osteoblasts. During fracture healing, however, both the periosteal and the endochondral processes are activated, leading to fracture healing that is temporally and morphologically normal, although the callus tissue is less prominent.     

Lipopolysaccharide impairs fracture healing: an experimental study in rats

Background It has been shown that trauma causes translocation of lipopolysaccharide (LPS) endotoxins from the gut. LPS has been identified as a major bacterial bone resorbing factor. The effects of LPS on bone healing are therefore of clinical interest, as trauma involving fractures followed by sepsis is a clinical scenario. We investigated the effects of systemic and local administration of LPS on the healing of femoral fractures in rats.

Animals and methods In 3 groups, each consisting of 9 rats, a mid-diaphyseal osteotomy/fracture of the femoral bone was performed and then nailed. In one group of animals, LPS was applied intraperitoneally (systemically), and in another group, LPS was applied locally at the fracture site. The third group served as a control. The animals were killed after 6 weeks, and the mechanical characteristics of the healing osteotomies were evaluated.

Results We found that LPS induced a hypertrophic and immature callus, as evaluated by bone mineral content and density. In the rats given LPS intraperitoneally, the mechanical strength characteristics were reduced, as evaluated by bending moment, rigidity, and energy absorption.

Interpretation The rats given LPS intraperitoneally reflect a clinical situation with fracture trauma and endotoxinemia. Our findings indicate that endotoxinemia may impair the fracture healing processes.

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Are distal radius fractures due to fragility or to falls? A consecutive case-control study of bone mineral density, tendency to fall, risk factors for osteoporosis, and health-related quality of life

Background A fracture of the distal radius is considered to indicate an increased risk of future fractures, especially a hip fracture. The main causes may be osteoporosis or a tendency to fall, separately or in combination.

Methods 93 women and 5 men with a recent radius fracture and the same number of controls were measured with a heel-DXL and asked to complete one questionnaire on their quality of life (SF-36), and one on risk factors.

Results The mean T-score of the patients was -2.1, and for the controls it was -1.9 (p = 0.3). The patients aged over 64 years had a history of falling more often than the corresponding controls (p = 0.01), but there was no difference in T-score. By contrast, patients 45-64 years of age showed a non-significant, lower T-score (p = 0.09), but there was no difference concerning their history of falling. For all other risk factors, no differences were found between the patients and the controls. There were significant differences between the patients and the controls in some of the functions in the SF-36, due to the radius fracture.

Interpretation This study indicates that the underlying cause of a distal radius fracture may be different in patients aged 45-64 years and those who are more than 64 years old.     

Long-standing increased bone turnover at the fixation points after anterior cruciate ligament reconstruction: a positron emission tomography (PET) study of 8 patients

Background A secure incorporation of the graft in a bone tunnel is a prerequisite for successful anterior cruciate ligament reconstruction. In this cross-sectional pilot study, we studied the healing process with positron emission tomography (PET) scanning.

Patients and methods 8 young patients underwent an anterior cruciate ligament reconstruction with a bonepatellar tendon-bone graft (BTB, n = 4) or a quadruple semitendinosus and gracilis graft (ST/G, n = 4). Regional bone turnover was quantified with an 18F-fluoride PET scan in each patient 1 day, 3 weeks, 7 months, or 22 months after surgery.

Results The highest activity level was found 3 weeks after surgery, but the activity at the femoral fixation points was markedly increased even after 7 months. The bone turnover was almost normalized 22 months after the operation.

Interpretation It would take at least 7 months until an anterior cruciate ligament graft, fixed with an interference screw, is completely incorporated. This finding is important for postoperative rehabilitation. Furthermore, PET is a feasible tool when studying new ways of fixing soft tissue to bone.     

Tartrate-resistant acid phosphatase 5b (TRAP 5b) as a marker of osteoclast activity in the early phase after cementless total hip replacement

Background After total hip replacement, increased bone metabolism is seen. A local periprosthetic osteopenia can be measured by dual-energy X-ray absorptiometry (DXA), but it is still unkown whether biochemical markers can be used to monitor the local remodeling at an earlier stage.

Patients and methods In this prospective study we compared the biochemical markers tartrate-resistant acid phosphatase 5b (TRAP 5b), bone ALP, osteocalcin and CrossLaps with periprosthetic DXA in 17 consecutive patients after uncemented total hip replacement.

Results We found a highly significant early increase in TRAP 5b after 2 weeks and 6 weeks, which was followed by a densitometrically detectable decrease in bone mineral density after 26 weeks, especially in periprosthetic section Gruen zone 7. Bone ALP and osteocalcin levels as markers of osteoblast activity, and also Cross-Laps as a further marker of osteoclast activity, did not appear to allow any significant prediction of local bone remodeling.

Discussion Our findings show that TRAP 5b is a sensitive parameter for monitoring of osteoclast activity after cementless total hip replacement, and may predict local osteopenia.     

Outcome after treatment of complications of Gamma nailing: a prospective study of 554 trochanteric fractures

Background A high reoperation rate has been the main reason why Gamma nailing should not be recommended for routine use in the treatment of trochanteric fractures. We compared the outcome after reoperation to the outcome after primary surgery with Gamma nailing.

Methods In a series of 554 patients, we compared the outcome in 52 patients who were reoperated with that in 502 patients who had no reoperations. We assessed mortality, pain, walking ability and habitat at follow-up.

Results The most common reason for reoperation was new fracture around the implant (17), local pain after healed fracture (11), nonunion (9) and cut-out (8). A second reoperation was required in 9/52 patients. The mortality was significantly lower in the reoperated cases at 30 days and at 1-5 years, but not at 120 days, and there were no significant differences in the other outcome parameters.

Interpretation Reoperation did not lead to a worse clinical outcome, nor to increased mortality.     

Tibial intramedullary nails -- should they be removed? A retrospective study of 71 patients

Background Anterior knee pain and young age of the patient have been considered justification for removal of a tibial intramedullary nail. There have been few reports on the outcome after nail removal, however.

Patients and methods We studied 71 patients in whom 72 tibial nails had been removed. We used self-assess-ment questionnaires to evaluate the location, intensity, and frequency of pain before and after removal. The degree of satisfaction was scored on a visual analog scale.

Results 39 of 71 patients had less pain after removal of the nail, but were not asymptomatic. 14 patients had unaltered pain, and 18 patients had increased pain. 4 of 6 patients who had been treated with fasciotomy were not satisfied with the outcome of nail removal.

Interpretation The results of nail removal to alleviate pain are poor. Removal of a nail should not be undertaken unless there is a convincing indication.     

Flexible intramedullary nailing for stabilization of displaced midshaft clavicle fractures: technique and results in 87 patients

Background Elastic, stable intramedullary nailing (ESIN) with titanium nails is a promising minimally treatment for displaced midclavicular fractures, which may be an alternative to plate fixation (ORIF) or even nonoperative treatment. We describe the surgical technique and outcome in 87 patients.

Methods The nail was inserted at the medial inferior end of the clavicle in 83 patients and in the acromial end in 12 patients. An open fracture reduction via an additional small incision was necessary in 53 patients and closed manoeuvre was successful in 42. Implant removal was performed in 82 patients.

Results The functional status of 87 patients after 13 months reached 6.8 (0-43) points on the DASH score and 81 (46-100) points on the self-reported Constant score. The fracture healed in correct anatomical axis in 80 of 87 patients, 2 cases ended in a nonunion. Implant migration of the nail occurred in 4 patients, who required early implant removal. Repeated nailing was necessary in 2 patients in whom the nail missed the lateral medullar canal, and plate fixation was necessary in 2 other patients who had secondary dislocation after early nail removal.

Interpretation Flexible intramedullary nailing, a minimally invasive technique for stabilization of displaced midshaft clavicle fractures, has minor risks and complications.     

One fracture is enough! Experience with a prospective and consecutive osteoporosis screening program with 239 fracture patients

Background Fracture and low bone mineral density both have strong predictive value for future fractures. The risk of future fractures can be reduced by medi-cal treatment if patients with osteoporosis are identified, for example by screening fracture patients for low bone mineral density. We suggest that these screening rou-tines be organized at orthopedics departments and we report our experience with such a screening system.

Patients and methods We screened all patients between 50-75 years of age with a wrist, vertebral, prox-imal humerus, or hip fracture visiting our orthopedics department by measuring bone mineral density (BMD) using DEXA scans. After diagnosis, the patients were referred to their primary care physician for treatment.

Results Between November 1, 2002, and October 31, 2003, 239 patients were investigated and only 13% had normal BMD values. 45% of the patients were diagnosed with osteopenia and 42% with osteoporosis.

Interpretation Screening of fracture patients who visit an orthopedics department appears to be an effec-tive way of identifying individuals with low bone min-eral density. The screening routines can be organized as an osteoporosis team consisting of a doctor, a nurse and a secretary at each department. Today, these patients are largely undetected and untreated—at least in our region. In our series, only 13 patients had been DEXA-scanned and were treated by antiresorptive drugs at the time of fracture. ▪     

Mechanical Properties of Fractured and Intact Rat Femora Evaluated by Bending, Torsional and Tensile Tests

Mechanical properties of healing fractures and growing, intact bones were studied in male rats aged 8 weeks at the beginning of the study period. A standardized, closed fracture was produced in the middle of the left femur. The fracture was not immobilized. At various intervals after the fracture, the healing fractured femora and the contralateral, intact femora were subjected to bending, torsional and tensile tests.

The fractured femora regained the strength and the ultimate deformation of the contralateral, intact femora after about 8 weeks when tested in bending, and after about 13 weeks when tested in torsion. In the first phases of fracture repair, the healing fractures could resist more torsional than bending load, whereas the opposite was found for solidly consolidated fractures and intact bones.

For intact bones, the ultimate bending and torsional moments increased with increase in age and weight of the animals, whereas the ultimate angular deformation remained constant. The ultimate bending and torsional stresses (bone material strength) increased to reach a plateau when the rats were about 14 weeks old. No significant differences were observed between the bending, torsional and tensile test methods. For the evaluation of fracture repair, each test has its particular application.     

Low metacarpal index predicts hip fracture: a prospective population study of 3,561 subjects with 15 years of follow-up

Background Metacarpal index (MCI), measured from hand radiographs as the ratio between combined cortical thickness and bone diameter, has been suggested for assessment of bone mass and risk of osteoporotic fracture. We studied MCI for its ability to predict hip fractures.

Methods Hand radiographs were taken and MCI determined in 3,561 subjects from a representative population sample of 8,000 Finns who were 30 years of age or over in 1978-80. Record linkage to the National Hospital Discharge Register identified 117 subjects who had been hospitalized for primary treatment of hip fracture by the end of 1994.

Results High age, low body mass index, tall stature and smoking at baseline showed, independently of each other, significant associations with low MCI. Low MCI was a strong predictor of hip fracture. When adjusted for all potential confounding factors, the relative risk of hip fracture per decrement of MCI by one standard deviation (0.1) was 1.5 (95% CI 1.2-1.8).

Interpretation Low MCI is associated with known risk factors of osteoporosis and predicts hip fracture. Since hand radiographs are easily available at low cost, measurements of MCI can be used as an alternative approach to find osteoporotic individuals with a high risk of hip fracture. ▪     

Influence of Age on Mechanical Properties of Healing Fractures and Intact Bones in Rats

Mechanical properties of fractured and intact femora have been studied in young and adult, male rats. A standardized, closed, mid-diaphyseal fracture was produced in the left femur, the right femur serving as control. The fracture was left to heal without immobilization. At various intervals, both fractured and intact femora were loaded in torsion until failure.

The fractured femora regained the mechanical properties of the contralateral, intact bones after about 4 weeks in young and after about 12 weeks in adult rats. For intact bones, both the ultimate torsional moment (strength) and the torsional stiffness increased with age of the animals, whereas the ultimate torsional angle remained unchanged. For bone as a material, however, the ultimate torsional stress (strength) and the modulus of rigidity (stiffness) increased with age only in young rats, being almost constant in the adult animals.

The various biomechanical parameters of the healing fractures did not reach those of the contralateral, intact bones simultaneously. The torsional moment required to twist a healing femoral fracture 20 degrees (0.35 radians), a deformation close to what an intact femur can resist, proved to be a functional and simple measure of the degree of fracture repair in rats.     

Cement is recommended in intralesional surgery of giant cell tumors: a Scandinavian Sarcoma Group study of 294 patients followed for a median time of 5 years

Background Giant cell tumors of bone rarely metasta-size but often recur locally after surgery. There is limited knowledge about the risk of recurrence related to different types of treatment.

Patients and methods We analyzed factors affecting the local recurrence rate in 294 patients with giant cell tumors of the extremities using prospectively collected material from 13 centers. The median follow-up time was 5 (0.2-18) years.

Results A local recurrence was diagnosed in 57 of 294 patients (19%). The overall 5-year local recurrence rate was 0.22. Univariate analysis identified young age and intralesional surgery to be associated with a higher risk of recurrence. Based on multivariate analysis, the relative risk was 2.4-fold for intralesional surgery compared to more extensive operative methods. There was no correlation between tumor size, tumor extension, sex of the patient, tumor location, or fracture at diagnosis and outcome. In the subgroup of 200 patients treated with intralesional surgery, the method of filling (cement or bone) was known for 194 patients and was statistically highly significant in favor of the use of cement.

Interpretation Intralesional surgery should be the first choice in most giant cell tumors, even in the presence of a pathological fracture. After thorough evacuation, the cavity should be filled with cement.     

Safe fixation with two acetabular screws after Ganz periacetabular osteotomy

Background and purpose With Ganz periacetabular osteotomy, the osteotomized acetabular fragment is reoriented in an adducted, extended, and rotated position. The acetabular fragment is fixated with 2 screws and the patients are allowed 30 kg of weight bearing immediately after surgery. We were interested in examining the stability of the reoriented acetabulum after Ganz osteotomy; thus, the migration of the acetabular fragment was assessed by radiostereometry.

Patients and methods 32 dysplastic patients (27 females; 32 hips) were included in the study. Median age was 39 (20-57) years. Radiostereometric examinations were done at 1 week, 4 weeks, 8 weeks and 6 months. Data are presented as mean (SD).

Results 6 months postoperatively, the acetabular fragment had migrated 0.7 (0.8) mm medially, and 0.7 (0.5) mm proximally. Mean rotation in adduction was 0.5° (1.3). In other directions, mean migration was below 0.5 mm/°. There were no statistically significant differences in migration at 8 weeks and 24 weeks postoperatively regarding translation and rotation.

Interpretation Due to the limited amount of migration, we find our postoperative partial weight-bearing regime safe.