Antero Natri
University of Vermont
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Calcified Tissue International | 1999
Jari Parkkari; Pekka Kannus; Mika Palvanen; Antero Natri; J. Vainio; Heikki Aho; Ilkka Vuori; Markku Järvinen
Abstract. The objectives of this study were to learn how hip fracture patients fall, and to compare the mechanics of their falls with those falls that did not result in hip fracture. In this way we sought to obtain reliable insight into the etiology and pathogenesis of hip fracture and fracture prevention. A total of 206 consecutive patients with fresh hip fracture and 100 controls were interviewed and examined between October 1994 and May 1996. The only inclusion criterion was that the fracture had occurred within 24 hours of hospital admittance. The control subjects were admitted from the same community after an accidental fall that did not result in hip fracture. The characteristics of the accident were determined by personal interview and examination of the patients within 24 hours of the event. In 98% of the hip fracture patients, the fracture was a result of a fall. The majority of the patients (76%) reported that they had fallen directly to the side. Forty-eight fracture cases had one or more eyewitnesses and their reports supported this observation. In 56% of the hip fracture patients, a fresh subcutaneous hematoma was seen on the greater trochanter of the proximal femur; such a hematoma was rare in the controls (6%) (P < 0.001), and this gave evidence for the direct impact of the greater trochanter during the fall of the hip fracture subjects. Most of the elderly fallers who fractured a hip did not manage to break the fall, e.g., with an outstretched arm. In conclusion, our results suggest that a typical hip fracture is the result of a fall and a subsequent impact on the greater trochanter of the proximal femur. The clinical implication of this finding is that effective prevention of hip fractures could be achieved by the diminution of the number and severity of falls of the elderly. We suggest that the severity of the falls (impacts on the greater trochanter) could be decreased by an external hip protector.
Scandinavian Journal of Medicine & Science in Sports | 2007
Pekka Kannus; L. Józsa; Antero Natri; Markku Järvinen
Since a tendon is a living tissue, it is not a surprise that tendon shows the capacity to adapt its structure and mechanical properties to the functional demands of the entire muscle‐tendon unit. However, compared with muscle, the experimental knowledge of the effects of strength or endurance‐type training on tendon tissue is scarce and clinical human experiments are completely lacking (1). Research should, however, be able to improve the true understanding of the biomechanical, functional, morphological and biochemical changes that occur in tendons due to training and physical activity, since understanding of the basic physiology of a tissue is the key to understanding its pathological processes (1,2). Compared with muscle tissue, the metabolic turnover of tendon tissue is many times slower due to poorer vascularity and circulation (1, 3). The adaptive responses of tendons to training are therefore also slower than those in muscles, but they may finally be considerable if the time frame is long enough (3, 4).
Journal of Bone and Joint Surgery, American Volume | 1999
Pekka Kannus; Antero Natri; Timo Paakkala; Markku Järvinen
BACKGROUND We determined prospectively the long-term outcomes of nonoperative treatment of chronic patellofemoral pain syndrome. METHODS Of forty-nine patients in a prospective, randomized, double-blind study of unilateral chronic patellofemoral pain syndrome in the knee, forty-five were reexamined seven years after the initial trial of treatment. In the earlier trial, the short-term (six-month) effects of intra-articular injections of glycosaminoglycan polysulfate combined with intensive quadriceps-muscle exercises were compared with those of injections of a placebo combined with exercises and with those of exercises alone. At seven years, the follow-up consisted of standardized subjective, functional, and clinical assessments and muscle-strength measurements as well as magnetic resonance imaging, radiography, and bone-densitometry measurements of the knee. RESULTS At six months, complete subjective, functional, and clinical recovery had occurred in almost three-fourths of the patients and, with the numbers available for study, neither significant nor clinically important differences among the three initial treatment groups were detected. The subjective and functional parameters showed few changes between six months and seven years; almost three-fourths of the patients still had full subjective and functional recovery at the time of the latest follow-up. However, according to the physicians clinical evaluation, the number of patients who had no symptoms on the patellar compression and apprehension tests decreased over time, from forty-two (93 percent) and forty (89 percent) of forty-five patients at six months to thirty (67 percent) and thirty-one (69 percent) at seven years; these changes were significant (p = 0.002 and p = 0.023, respectively). The number of patients who had crepitation on the patellar compression test increased over time, from twenty-six (58 percent) at six months to thirty-six (80 percent) at seven years (p = 0.021). The physicians overall assessment showed a similar trend, with thirty-four patients (76 percent) having had complete recovery at six months compared with thirty (67 percent) at seven years; however, with the numbers available, this change was not significant (p = 0.420). Magnetic resonance imaging, performed for thirty-seven patients, revealed no abnormalities in twenty-four (65 percent), mild abnormalities in four (11 percent), moderate abnormalities (a 25 to 75 percent decrease in the thickness of the cartilage) in seven (19 percent), and overt patellofemoral osteoarthritis in two (5 percent) at seven years. CONCLUSIONS The seven-year overall outcome was good in approximately two-thirds of the patients. However, the remaining patients still had symptoms or objective signs of a patellofemoral abnormality.
Sports Medicine | 1999
Antero Natri; Bruce D. Beynnon; Carl F. Ettlinger; Robert J. Johnson; Jasper E. Shealy
In spite of the fact that the overall incidence of alpine ski injuries has decreased during the last 25 years, the incidence of serious knee sprains usually involving the anterior cruciate ligament (ACL) has risen dramatically since the late 1970s. This trend runs counter to a dramatic reduction in lower leg injuries that began in the early 1970s and to date has lowered the risk of injury below the knee by almost 90%.One of the primary design objectives of modern ski boots and bindings has been to protect the skier from tibia and ankle fractures. So, in that sense, they have done an excellent job. However, despite advances in equipment design, modern ski bindings have not protected the knee from serious ligament trauma.At the present time, we are unaware of any binding design, settings or function that can protect both the knee and lower extremities fromserious ligament sprains. No innovative change in binding design appears to be on the horizon that has the potential to reduce the risk of these severe knee injuries. Indeed, only 1 study has demonstrated a means to help reduce this risk of serious knee sprains, and this study involved education of skiers, not ski equipment.Despite the inability of bindings to reduce the risk of severe knee injuries there can be no doubt that improvement in ski bindings has been the most important factor in the marked reduction in incidence of lower leg and ankle injuries during the last 25 years. The authors strongly endorse the application of present International Standards Organisation (ISO) and American Society for Testing and Materials (ASTM) standards concerning mounting, setting and maintainingmodern ’state of the art’ bindings.
The American Journal of Medicine | 2000
Jari Parkkari; Antero Natri; Pekka Kannus; Ari Mänttäri; Raija Laukkanen; Heidi Haapasalo; Arja Nenonen; Matti Pasanen; Pekka Oja; Ilkka Vuori
PURPOSE To study the effects of regular walking during a golf game on various health and fitness indicators in middle-aged men. METHODS Study subjects were 55 healthy male golfers aged 48 to 64 years who had been sedentary during the 7 months before the study, and 55 age-matched, similarly sedentary controls. During the 20-week study, those in the intervention group were encouraged to play golf two to three times a week; the controls were not. Measurements of body composition, cardiorespiratory performance, motor and musculoskeletal fitness, blood pressure, and serum lipid, glucose, and insulin levels were obtained at baseline and after the 20-week study. RESULTS Walking during a golf game was a practical and safe form of physical activity with high adherence. It significantly increased aerobic performance and trunk muscle endurance, with a net difference (pretraining to posttraining change between the golfers and controls) of 36 seconds (95% confidence interval [CI]: 19 to 53 seconds, P < 0.001) for treadmill walking time and 13 seconds (95% CI: 2 to 24 seconds, P = 0.02) for static back extension. In addition, regular walking favorably affected body composition, including reductions in weight of 1.4 kg (95% CI: 0.6 to 2.1 kg, P < 0.001), in waist circumference of 2.2 cm (95% CI: 1.0 to 3.3 cm, P < 0.001), and in abdominal skin fold thickness of 2.2 cm (95% CI: 0.9 to 3.4 cm, P = 0.001). Golfers also had significantly greater increases in serum high-density lipoprotein (HDL) cholesterol levels and in the ratio of HDL cholesterol to total cholesterol. CONCLUSIONS Regular walking had many positive effects on the health and fitness of sedentary middle-aged men. Walking during a golf game is characterized by high adherence and low risk of injury and is therefore a good form of health-enhancing physical activity.
Spine | 2006
Jaana Suni; Marjo Rinne; Antero Natri; Matti Pasanen Statistisian; Jari Parkkari; Hannu Alaranta
Study Design. A randomized controlled study with 12 months intervention. Objective. To study the effectiveness of a training intervention with emphases on the control of lumbar neutral zone (NZ) and behavior modeling as secondary prevention of low back pain (LBP) and disability. Summary of Background Data. Improving the control of lumbar NZ and enhancing muscle activation patterns ensuring spinal stability have been proposed as means for secondary prevention of LBP and disability. In addition, cognitive behavior interventions have been shown to lower the risk of recurrence of LBP and long-term disability. Methods. Middle-aged working men with recent LBP but without severe disability were randomly allocated to either a training (TG, n = 52) or control group (CG, n = 54). The aim was to exercise twice a week for 12 months, once guided and once independently. The outcome measures were the changes in intensity of LBP, disability, self-evaluated future work ability, and neuromuscular fitness. Results. The intensity of LBP decreased significantly more (39%) in the TG than in CG at 12 months. The proportion of subjects with negative expectations about their future work ability decreased in both groups at 6 and 12 months; however, the proportion was significantly bigger in TG compared with CG (P = 0.028). There effects on disability indexes and fitness were not statistically significant. Conclusions. Controlling lumbar NZ is a specific form of exercise and daily self-care with potential for prevention of recurrent nonspecific LBP and disability among middle aged working men.
Histochemical Journal | 1998
Pekka Kannus; Laszlo Jozsa; Tero A.H. Järvinen; Teppo L. N. Järvinen; Martti Kvist; Antero Natri; Markku Järvinen
The study assessed immunohistochemically the location and distribution of various non-collagenous matrix proteins (fibronectin, laminin, tenascin-C, osteocalcin, thrombospondin-1, vitronectin and undulin) in musculoskeletal tissues of rat. Fibronectin and thrombospondin-1 were found to be ubiquitous in the studied tissues. High immunoreactivity of these proteins was found in the extracellular matrix of the anatomical sites where firm bindings are needed, i.e. between muscle fibres and fibre bundles, between the collagen fibres of a tendon and at myotendinous junctions, osteotendinous junctions and articular cartilage. Tenascin-C was found in the extracellular matrix of regions where especially high forces are transmitted from one tissue component to the other, such as myotendinous junctions and osteotendinous junctions. Laminin was demonstrated in the basement membranes of the muscle cells and capillaries of the muscle–tendon units. Osteocalc in immunoreactivity concentrated in the extracellular matrix of areas of newly formed bone tissue, i.e. in the subperiosteal and subchondral regions, osteoid tissue and mineralized fibrocartilage zone of the osteotendinous junction. Mild vitronectin activity could be seen in the extracellular matrix of the osteotendinous and myotendinous junctions, and high activity around the bone marrow cells. Undulin could be demonstrated in the extracellular matrix (i.e. on the collagen fibres) of the tendon and epimysium only. However, it was co-distributed with fibronectin and tenascin-C. Together, these findings on the normal location and distribution of these non-collagenous proteins in the musculoskeletal tissues help to form the basis of knowledge against which the location and distribution of the these proteins in various pathological processes could be compared.
Scandinavian Journal of Medicine & Science in Sports | 2007
K. Pasanen; Jari Parkkari; Pekka Kannus; L. Rossi; Mika Palvanen; Antero Natri; Markku Järvinen
The purpose of this prospective study was to examine the incidence, nature, causes, and severity of injuries in female floorball. Three hundred and seventy‐four licensed female floorball players from Finnish top leagues were observed prospectively for one season (6 months). The practice and game hours of floorball were recorded on an exercise diary. All injuries were registered with a structured questionnaire and verified by a physician. During the study period, 133 out of the 374 (35%) players sustained 172 injuries. The injury incidence was 1.8 per 1000 practice hours and 40.3 per 1000 game hours. Of all injuries, 70% were traumatic and 30% were from overuse. The most common injury type was joint sprain (27%). The most commonly injured sites were the knee (27%) and ankle (22%). Twenty‐one of the knee injuries (46%) were serious including 10 anterior cruciate ligament (ACL) ruptures. Eight of ACL ruptures occurred during floorball games, giving an ACL rupture incidence of 3.6 per 1000 game hours. Eleven injuries (6%) needed hospital admission. The study attested that injury rate in floorball game is very high. Injury prevention strategies in female floorball should be targeted at injuries occurring at the knee and ankle.
American Journal of Epidemiology | 1999
Pekka Kannus; Mika Palvanen; Seppo Niemi; Jari Parkkari; Antero Natri; Ilkka Vuori; Markku Järvinen
To increase knowledge about recent trends in the number and incidence of various fall-induced injuries among older adults, the authors selected from the National Hospital Discharge Register all patients 60 years of age or older who were admitted to hospitals in Finland for primary treatment of a first fall-induced severe head injury during 1970-1995. Similar patients aged 30-39 years served as a reference group. For the study period, the number and incidence (per 100,000 persons) of fall-induced severe head injuries in Finnish persons 60 years of age or older increased considerably (554 and 85, respectively, in 1970 compared with 1,393 and 144, respectively, in 1995). The age-adjusted incidence of these injuries also increased in women, from 80 in 1970 to 125 in 1995, and in men, from 102 in 1970 to 147 in 1995. In the reference group (patients aged 30-39 years), the absolute numbers and incidences of similar injuries did not show consistent trend changes over time. We conclude that the number of fall-induced severe head injuries in elderly Finnish women and men is increasing at a rate that cannot be explained simply by demographic changes, and therefore vigorous preventive measures should be instituted at once to control the increasing burden of these devastating injuries.
American Journal of Sports Medicine | 1999
Antero Natri; Harri Sievänen; Jari Parkkari; Pekka Kannus; Kimmo Vihtonen; Juha Koskela; Markku Järvinen
The majority of tibial shaft fractures are the result of traffic accidents, and these fractures are rare in athletes other than those involved in motor sports. In weightlifting, fractures have usually been described to occur in the lumbar ring apophysis and wrist. This report describes a spontaneous shaft fracture of the tibia during weightlifting. We examined in detail as to whether there were any abnormalities in the patient’s metabolic, hormonal, and bone mineral status. The possible injury mechanisms that led to this fracture were reviewed.