Quantitative 3D MRI reveals limited intra-lesional bony overgrowth at 1 year after microfracture-based cartilage repair.

OBJECTIVE: Intra-lesional bony overgrowth (BO) identified during or following cartilage repair treatment is being frequently described through subjective reports focusing primarily on incidence. Our objective was to quantify the exact volume of intra-lesional BO at 12 months post-cartilage repair treatment, to determine if a correlation exists between the extent of BO and clinical outcomes, and to visualize and characterize the BO. DESIGN: MRI scans were systematically obtained during a randomized clinical trial for cartilage repair (Stanish et al., 2013) that compared two microfracture-based treatments in 78 patients. Semi-automated morphological segmentation of pre-treatment, 1 and 12 months post-treatment scans utilizing a programmed anatomical atlas for all knee bone and cartilage structures permitted three-dimensional reconstruction, quantitative analysis, as well as qualitative characterization and artistic visualization of BO. RESULTS: Limited intra-lesional BO representing only 5.8 ± 5.7% of the original debrided cartilage lesion volume was found in 78 patients with available MRIs at 12 months. The majority (80%) of patients had very little BO (<10%). Most occurrences of BO carried either spotty (56.4%) or planar (6.4%) morphological features, and the remaining balance (37.2%) was qualitatively unobservable by eye. Pre-existing BO recurred at 12 months in the same intra-lesional location in 36% of patients. No statistical correlations were found between BO and clinical outcomes. CONCLUSIONS: Intra-lesional BO following microfracture-based treatments may not be as severe as previously believed, its incidence is partly explained by pre-existing conditions, and no relationship to clinical outcomes exists at 12 months. Morphologically, observable BO was categorized as comprising either spotty or planar bone.

Knee effusion affects knee mechanics and muscle activity during gait in individuals with knee osteoarthritis.

OBJECTIVE: To test the hypothesis that knee effusion presence in those with knee osteoarthritis (OA) alters knee joint muscle activation patterns and sagittal plane mechanics during gait. METHODS: Thirty-five patients with medial compartment knee OA were assessed for the presence of effusion using a brush test. Based on the results, they were assigned to the knee effusion (n = 17) and no knee effusion (n = 18) groups. Electromyograms from seven lower extremity muscles (lateral and medial gastrocnemius, vastus lateralis and medialis, rectus femoris and the lateral and medial hamstrings), leg motion and ground reaction forces were recorded during self-selected walking. Isometric knee extensor, plantar flexor and knee flexor strength were measured. Discrete measures from angular knee motion and net external moment of force waveforms were identified. Principal component analysis extracted electromyographic waveform features. Analysis of variance models tested for main effects (group, muscle) and interactions (α = 0.05). Bonferroni post-hoc testing was employed. RESULTS: No differences in age, body mass index, knee pain, Western Ontario McMaster Osteoarthritis Index scores, gait velocity and muscle strength were found between groups (P > 0.05). Individuals with effusion had a greater overall quadriceps activation and prolonged hamstring activation into mid-stance (P < 0.05). Knee joint flexion angles were higher (P < 0.05) and net external knee extension (KE) moments in mid to late stance lower in the effusion group. CONCLUSION: Quadriceps and hamstrings activation during walking were altered when effusions were present. Increased knee flexion (KF) angles and decreased KE moment in mid-late stance provide a mechanical explanation for the effect of joint effusion on muscle activation in those with knee OA.

The neuromuscular demands of altering foot progression angle during gait in asymptomatic individuals and those with knee osteoarthritis.

OBJECTIVES: To determine the immediate effects of a toe-out foot progression angle modification during gait on the major lower limb muscle activation characteristics and to establish whether asymptomatic individuals and those with moderate knee OA have similar responses. DESIGN: Seventeen patients with knee OA and 20 asymptomatic control subjects participated. Informed consent was obtained. Electromyographic (EMG) recordings were acquired from the lateral and medial gastrocnemii, vastus lateralis, vastus medialis, rectus femoris and the lateral and medial hamstrings during neutral and toe-out walking conditions. The EMG waveforms were amplitude normalized to maximal voluntary isometric contractions and time normalized to the gait cycle. Principal component analysis extracted principal waveform features. Analysis of variance models tested for main effects and interactions. Bonferroni post hoc testing was employed (alpha=0.05). RESULTS: Both groups altered foot progression angle by approximately 15 degrees during toe-out walking (P<0.05). A shift in gastrocnemius activation towards later stance (P<0.05) and increased magnitude and duration of quadriceps activation (P<0.05) was found. A differential activation occurred in the overall magnitude and principal shape of the lateral and medial hamstring musculature in the asymptomatic group only (P<0.05). Significant group differences were shown in each muscle analysis (P<0.05). CONCLUSION: Neuromuscular demands of adopting a toe-out gait differ from a neutral foot progression angle. Demands also differ between asymptomatic controls and patients with moderate knee OA. These findings have relevance for altered joint loading and changes in metabolic cost of this gait modification in individuals with knee OA.

Neuromuscular alterations during walking in persons with moderate knee osteoarthritis.

This paper compared the neuromuscular responses during walking between those with early-stage knee osteoarthritis (OA) to asymptomatic controls. The rationale for studying those with mild to moderate knee OA was to determine the alterations in response to dynamic loading that might be expected before severe pain, joint space narrowing and joint surface changes occur. We used pattern recognition techniques to explore both amplitude and shape changes of the surface electromyograms recorded from seven muscles crossing the knee joint of 40 subjects with knee OA and 38 asymptomatic controls during a walking task. The principal patterns for each muscle grouping explained over 83% of the variance in the waveforms. This result supported the notion that the main neuromuscular patterns were similar between asymptomatic controls and those with OA, reflecting the specific roles of the major muscles during walking. ANOVA revealed significant (p<0.05) differences in the principal pattern scores reflecting both amplitude and shape alterations in the OA group and among muscles. These differences captured subtle changes in the neuromuscular responses of the subjects with OA throughout different phases of the gait cycle and most likely reflected changes in the mechanical environment (joint loading, instability) and pain. The subjects with OA attempted to increase activity of the lateral sites and reduce activity in the medial sites, having minimal but prolonged activity during late stance. Therefore, alterations in neuromuscular responses were found even in this high functioning group with moderate knee OA.

Energy intake: its relationship to colon cancer risk.

A case-control study was conducted to assess the role of diet in the etiology of colon cancer. Diet was measured by means of a comprehensive quantifiable food frequency history instrument in 246 cases and 484 controls drawn from the general population of Utah. Each subject's diet was described by major nutrient groups and total energy based on the nutritional content of foods reported. Cases reported higher daily food intake 5 years preceding diagnosis than controls [men, rate ratio (RR) = 2.5; women, RR = 3.6], as measured by total energy content of the diet. Higher risk of colon cancer with increasing energy intake was independent of stage of disease at diagnosis and obesity, as measured by body mass. Fat, protein, and carbohydrate intake all had elevated RRs but could not be assessed as risk factors independent of energy intake because of their strong correlations with total calories. Due to the higher energy intake of the cases, odds ratios for the daily intake of dietary fiber and vitamins A and C were also greater than 1. However, adjusting for caloric intake removed this effect, and dietary fiber showed a weak protective effect. Total energy intake must be evaluated before attempting to assign a causal role to any food or nutrient that may be postulated to play a role in colon cancer.

Obesity is associated with prolonged activity of the quadriceps and gastrocnemii during gait.

PURPOSE: To examine the effect of obesity and its potential interaction with knee OA presence on the electromyography patterns of the major knee joint periarticular muscles during walking. SCOPE: One hundred and eighteen asymptomatic adults and 177 adults with moderate knee osteoarthritis were subdivided into categories of healthy weight (n = 77; 20 kg/m(2) < BMI < 25 kg/m(2)), overweight (n = 117; 25 kg/m(2) ⩽ BMI < 30 kg/m(2)), and obese (n = 101; BMI ⩾ 30 kg/m(2) based on their body mass index (BMI). All individuals underwent a three-dimensional gait analysis. Surface electromyograms from the lateral and medial gastrocnemii, lateral and medial hamstrings, vastus lateralis, vastus medialis, and rectus femoris were recorded during self-selected speed walking. Principal component analysis was used to extract major features of amplitude and temporal pattern variability from the electromyograms of each muscle group (gastrocnemii, quadriceps, hamstrings separately). Analysis of variance models tested for main BMI category effects and interaction effects for these features (α = 0.05). Statistically significant BMI category (i.e. obesity) effects were found for features that described more prolonged activations of the gastrocnemii and quadriceps muscles during the stance phase of gait with obesity (P < 0.05). CONCLUSIONS: Obesity was associated with prolonged activation of quadriceps and gastrocnemii, which can result in prolonged knee joint contact loading, and thereby may contribute to the predisposition of knee OA development and progression in obese individuals.

Familial prostatic cancer risk and low testosterone.

We investigated whether familial factors influence 1) the incidence of prostatic cancer and 2) the plasma content of sex steroids. A 4-fold higher relative risk for the development of prostatic cancer was observed for brothers (n = 257) of prostatic cancer cases (n = 150) compared to their brothers-in-law (n = 202) and males in the general population of the state Utah. The intraclass correlation for plasma testosterone content [intraclass correlation coefficient (r1) = 0.51; P less than 0.01] and the apparent free testosterone concentration (r1 = 0.54; P less than 0.01) were highly significant in nonendocrinologically treated cases and their brothers. Further, sons and their fathers had significant intraclass correlations for both plasma dihydrotesterone (r1 = 0.83; P less than 0.01) and the ratio of testosterone to dihydrotestosterone (r1 = 0.46; P less than 0.05). Probands and their brothers, and sons of the patients with the disease had significantly lower plasma testosterone levels than controls of comparable age. This is the first documentation indicating that familial (possibly genetic) factors are potent risk factors for predisposing men to the development of prostatic cancer and in regulating the plasma content of androgens. Our results indicate that plasma androgen levels in families with prostatic cancer are clustered in the lower range of the normal population. They also suggest that plasma androgen content is more similar within each family with the cancer than among the families without cancer.

Predictors of survival in subjects with chronic airflow limitation.

In a study of chronic airflow limitation, we followed 140 subjects living in Utah at altitudes of 1,300 to 1,500 meters for seven to 13 years. Twelve-year survival probabilities were determined and compared with an age- and sex-matched Utah population. The lowest 12-year survival probability was 0.40 for those patients with a forced expiratory volume in one second/forced vital capacity (FEV1/FVC) of less than or equal to 0.40, indicating that there is much variability in survival. Other indicators of a lower survival probability (and increased death risk ratio) were an FEV1 percent predicted less than or equal to 50, an FEV1 less than or equal to 1.5 liters, male gender, partial pressure of oxygen (PO2) [exercise] less than or equal to 50 mm Hg, partial pressure of carbon dioxide (PCO2) [rest] greater than 39 mm Hg, PCO2 (exercise) greater than 39 mm Hg, FVC percent predicted less than or equal to 80, PO2 (rest) less than or equal to 55 mm Hg, and a carbon monoxide diffusing capacity (DLCO) percent predicted less than or equal to 80. Current smokers had a poorer survival probability than the reference population and an increased death risk when compared with the nonsmokers in the study. Pack/years of smoking also affected survival. Other variables associated with reduced survival were a diagnosis of chronic bronchitis combined with emphysema, more rapid annual declines in the FEV1 and/or FVC, low alpha 1-antitrypsin levels, a 20 percent improvement in FEV1 following the use of a bronchodilator aerosol, and a lower socioeconomic class. Differences between these findings and those noted in other studies are in the main due to differences in the characteristics (such as age, diagnosis, and extent of disease) of the patients in the study populations. The findings have relevance in estimating a patient's prognosis and for developing guidelines for disability determination purposes.

Familial effects on plasma sex-steroid content in man: testosterone, estradiol and Sex-hormone-binding globulin.

We investigated whether familial factors influence the plasma content of sex-steroids and sex-hormone-binding globulin (SHBG) in 98 adult males of 66 families. They had no apparent endocrine dysfunction, The 0800-1100 hr plasma levels of testosterone, 5 alpha-dihydrotestosterone (DHT), estradiol-17 beta (E2) and estrone (E1) were measured by radioimmunoassay. The free fractions of E2 and testosterone were determined by equilibrium dialysis, and binding capacity of SHBG was also calculated. The data were analyzed by analysis of variance. We observed that the differences in the plasma content of testosterone (p = .02). SHBG binding capacity (p = 0.1), and E2 (p = 0.3), free E2 index (p = .05) were all substantially less variable within groups of brothers than among non-brothers. The variability of the plasma concentration of DHT, free testosterone and E1 was not significantly less within brothers than among non-brothers. The correlation between either plasma testosterone content (r = .14) or SHBG binding capacity (r = .12) and percent of ideal body weight was not significant statistically. Age had no effect on the results. Our data suggest that genetic and/or environmental factors may affect the plasma content of testosterone, E2 and SHBG binding capacity.

Rehabilitation of tendon injuries in sport.

Clinicians are faced with a growing number of athletes with injured tendons. Treatment of both acute and chronic injuries has proven to be quite complex. It is difficult to maintain the balance between resting the injured tendon and preventing atrophy of the surrounding muscles and joints. Questions also arise as to when the tendon should be strengthened and when the athlete is ready to return to full activity in sport. Through an awareness of the structural and mechanical properties of the tendon, an exercise programme for the rehabilitation of tendon injuries has been developed. It is recommended that this programme be used in combination with ice and other physical modalities. This approach will resolve most tendon injuries within 6 weeks of its implementation. The use of anti-inflammatory medications and surgery can only be recommended in select situations where more conservative measures are inadequate.

Risk factors and the prevalence of depression in Mormon women.

A cross-sectional study was conducted in the Utah metropolitan area in which a random sample of white, married women with children 14 years of age or younger were interviewed by telephone. Information was obtained on possible risk factors for depression and depression was measured using the Beck Depression Inventory (BDI). Prevalence of depression was compared in Mormon women (N = 143) who have a high percentage of career homemakers and non-Mormon (N = 36) who have a high percentage of women working outside the home. No difference in prevalence of depression was noted. Risk factors for depression in Mormon women were also studied. After adjusting for confounding, the risk factors were: Less education, little perceived caring from spouse, perception of having less than good health and having a low income. These findings are compared to other studies.

Overuse injuries in athletes: a perspective.

Injuries secondary to sporting activities have increased significantly in the past decade. Traditional treatment programs for these maladies have frequently failed to meet the physiological expectations of the athlete. Forced rest or immobilization result in predictable musculoskeletal atrophy with impaired function. Furthermore, the rehabilitation process has commonly focused on the management of the acute problem with minor attention to the etiology and pathomechanics of the injury (preventive medicine). Many sports injuries, as a result of overuse, can be avoided by scientific coaching and contemporary sports medicine.

Chronic compartment syndrome caused by aberrant fascia in an aerobic walker.

The following is a case presentation of a 36-yr-old female athlete who presented with the symptoms and signs of chronic anterior compartment syndrome. Pre-exercise and post-exercise tissue pressure measurements revealed increased compartment pressures in both of her anterior leg compartments. Aberrant fascial bands overlying and compressing the anterior compartments were discovered at the time of surgery. Fasciotomies led to complete recovery and return to previous levels of athletic activity. This is the first report of aberrant fascia as a cause of chronic anterior compartment syndrome.

A study of the biological behavior of the meniscus as a transplant in the medial compartment of a dog's knee.

A surgical procedure was developed such that a meniscus could be reimplanted in the medial compartment of canine knees. The medial meniscus was removed and reimplanted in one group of seven animals, removed and reimplanted with a glutaraldehyde-preserved bioprosthesis in a second group of five animals, and removed and replaced by an allograft meniscus preserved 2 to 3 weeks in tissue culture in a final group of ten animals. All animals were autopsied at 2 months and the knees were examined by gross dissection and histologic study of the joint capsule meniscal interface. Results showed that implantation by the surgical technique was effective and no loose bodies or partial detachments were found in the reimplantation or tissue culture-stored allogenic menisci. Allogenic menisci preserved in glutaraldehyde and termed a bioprosthesis attached to the joint capsule less satisfactorily. There was minimal inflammation of the synovium in any group at 2 months; however, the glutaraldehyde group showed repeated effusions at 1 and 2 weeks.

The aging athlete.

In summary, the purpose of this material is to demonstrate that the aging athlete does differ from the younger competitor in many facets. There are physiological, structural, and psychosocial differences which distinguish them as a unique entity in the athletic world. Despite the unavoidable alterations that the passage of time imposes on our bodies, these competitors are still capable of incredible performances of strength, skill, and endurance. In reference to injury, these athletes are at risk from both their current program and their past indiscretions. The literature strongly suggests that the greatest threat to the health of the aging athlete is not the aging process itself but rather inactivity. Astrand concurs with this and states that "there is less risk in activity than in continuous inactivity--it is more advisable to pass a careful physical examination if one intends to be sedentary in order to establish whether one's state of health is good enough to stand the inactivity." It appears that the body systems were designed to reinforce activity and when there is disuse, a large number of atrophic changes take place. It has been estimated that regular exercise may be able to retard the physiologic decline associated with old age as much as 50%. Taken in this light, exercise is truly a fountain of youth from which we can all rejuvenate ourselves. Science has proven that life does not begin at 40, but it has also demonstrated that it does not have to end there. As one author so aptly states, "Not too many years ago the words grandma and grandpa conjured images of rocking chairs and inactivity."(ABSTRACT TRUNCATED AT 250 WORDS)

An unusual cause of back pain in a young athlete. A case report.

Back pain in the young athlete is a common problem seen in many sport medicine clinics. Not only can this be a difficult problem for the physician to manage (due to inability to pinpoint the pathology), but it is a frustrating experience for the athlete, unable to compete or train effectively. The sport medicine physician must, therefore, always be alert and obsessed with obtaining a precise diagnosis to be followed by specific treatment. When presented with the adolescent athlete suffering with back pain, one must consider the full gamut of diagnostic possibilities. Mechanical or spondylogenic causes are most common; however, potentially more serious infective, metabolic, and neoplastic conditions should also be considered.

Medial epicondylitis. An electromyographic analysis and an investigation of intervention strategies.

Flexor and extensor muscle-tendon unit activity at the elbow during the golf swing was recorded from subjects with and without medial epicondylitis. There was no significant difference in total swing time between symptomatic (1.23 +/- 0.15 sec) and asymptomatic (1.15 +/- 0.13 sec) subjects nor between golfers with low (1 to 6 handicap, N = 8) and high (11 to 19 handicap, N = 8) scoring abilities. Symptomatic and asymptomatic subjects displayed similar electromyographic profiles for flexor and extensor muscles of the forearm. Electromyographic activity of the common extensor muscles was persistent throughout the four swing phases, ranging from 33.59% of maximum voluntary contraction at address to 58.77% at contact. Common flexor muscles produced a consistent burst of electromyographic activity during contact phase (flexor burst, 90.77% of maximum voluntary contraction). Symptomatic subjects' mean flexor muscle electromyographic activity was significantly greater than that of asymptomatic subjects in both address and swing phases. When forearm brace and oversized grips were imposed on symptomatic subjects, there was no significant difference in mean electromyographic magnitude or muscle activation pattern during the golf swing. Thus, the method of symptomatic relief of the intervention strategies tested is still in question.

The effects of static stretching exercises and stationary cycling on range of motion at the hip joint*.

The objective of this study was to compare the effects of static stretching exercises and stationary cycling on hip range of motion measures immediately following exercise and after a 15-min period of rest or continued activity. The results showed that both exercises performed for equal time periods resulted in hip range of motion increases with no significant difference (p < 0.05) between the immediate effects of the two exercises. Fifteen minutes of cycling or inactivity did not result in significant differences (p < 0.05) from the initial gains resulting from the stretching, but did result in significant increases in hip flexion for the group that continued cycling. Based on the results of this study, static stretching and cycling were equally effective for increasing range of motion and retaining the increase for a 15-min period in a controlled environment, independent of activity.J Orthop Sports Phys Ther 1984;6(2):104-109.

Low back pain in athletes: an overuse syndrome.

Back ache in athletes is exceedingly common. Fortunately, most of these pain syndromes are self-limiting. A precise analysis of the patient will allow an accurate diagnosis, which leads to an understanding of the natural history of that particular problem. Surgical intervention is very rarely necessary and reserved strictly for those problems that are completely recalcitrant to nonsurgical measures.

Lower leg, foot, and ankle injuries in young athletes.

Most injuries to the young athlete do have a benign natural course--complete resolution of the difficulty without sequelae. In order to develop a contemporary program of management of the more serious disorders in this active population, the practitioner must be certain to carefully analyze the injury and initiate a rapid course of action. A fracture of the tibia must be reduced, held aligned, and then rehabilitated. A compartment syndrome commonly demands early fasciotomy; the young athlete and his or her parents warrant a sensitive understanding from physicians to quell the anxiety that is paramount to all of these disorders.