We undertook a prospective study in 51 male patients aged between 17 and 27 years to ascertain whether immobilisation after primary traumatic anterior dislocation of the shoulder in external rotation was more effective than immobilisation in internal rotation in preventing recurrent dislocation in a physically active population.

Of the 51 patients, 24 were randomised to be treated by a traditional brace in internal rotation and 27 were immobilised in external rotation of 15° to 20°. After immobilisation, the patients undertook a standard regime of physiotherapy and were then assessed clinically for evidence of instability. When reviewed at a mean of 33.4 months (24 to 48) ten from the external rotation group (37%) and ten from the internal rotation group (41.7%) had sustained a futher dislocation. There was no statistically significant difference (p = 0.74) between the groups.

Our findings show that external rotation bracing may not be as effective as previously reported in preventing recurrent anterior dislocation of the shoulder.

Introduction: Preliminary data suggest that immobilization in external rotation may be effective in lowering the incidence of recurrence after first traumatic shoulder dislocation, with a zero reoccurrence rate reported at 15 months follow-up. The purpose of the present study was to ascertain whether this method could lower the incidence of recurrent dislocation in a young, very physically active population.

Methods: In an IRB approved prospective study, young males who sustained first traumatic shoulder dislocation were randomized to be treated for four weeks either using a traditional internal rotation brace or a new device which immobilizes the shoulder at 15 to 20 degrees of external rotation. Subjects were then treated according to a standard physical therapy protocol. Follow-up was done at five time points in the first year post dislocation. Subjects with clinically stable shoulders resumed full activity after three months. Differences in outcome were assessed by the chi square test.

Results: Thirty nine subjects participated in the study. Thirty of them were soldiers. Twenty four subjects were treated with external rotation braces. At follow-up of between 4 to 28 months, a new dislocation was documented in 8 of the 24 subjects immobilized in external rotation (33%) and in 5 of the 15 subjects immobilized in internal rotation (33 %). No statistical difference (p=1.0) was found between the instability rates of the two treatment groups.

Discussion: The present study indicates that even in a short-term follow-up the technique of immobilizing a first dislocation in external rotation was not effective in lowering the incidence of recurrent shoulder dislocations in a young, physically active population.

Excessive foot pronation has been considered to be related to anterior knee pain. We undertook a prospective study to test the hypothesis that exertional anterior knee pain is related to the static and dynamic parameters of foot pronation. Two weeks before beginning basic training lasting for 14 weeks, 473 infantry recruits were enrolled into the study and underwent two-dimensional measurement of their subtalar joint displacement angle during walking on a treadmill.

Of the 405 soldiers who finished the training 61 (15%) developed exertional anterior knee pain. No consistent association was found between the incidence of anterior knee pain and any of the parameters of foot pronation. While a statistically significant association was found between anterior knee pain and pronation velocity (left foot, p = 0.05; right foot, p = 0.007), the relationship was contradictory for the right and left foot. Our study does not support the hypothesis that anterior knee pain is related to excessive foot pronation.

Introduction The accuracy of ultrasonography has been reported to be high in diagnosing full thickness rotator cuff tears if measurements are made in both in the coronal and sagital planes. The purpose of this study is to determine how well pre-operative shoulder ultrasound rotator tear measurements when performed only in the coronal plane, the common practice in Israel, predicts the intra-operative surgical findings.

Materials and Methods Fifty consecutive patients who underwent open rotator cuff repairs were included in the study. All patients underwent a pre-operative ultrasound by the same experienced musculoskeletal ultrasoundist. Rotator cuff tears were measured in the coronal plane only. This was compared with the tear size measured intra-operatively. Regression analysis was done between the two variables.

Results The mean size of rotator cuff tears as determined by ultrasonography was 15.56±8.07mm and the measure size of the tears intraoperatively was 27.94±9.8 mm. The result of the regression analysis of the two variables was R2= 0.268405 for the first 25 patients and R2= 0.310309 for the second 25 patients.

Discussion Using ultrasound it is easy to visualize the extent of rotator tears in the coronal plane, but more time consuming to measure the extent in the sagital plane, where the tear may have its greatest extension. Ultrasound measurements tear measurements in this study, made only in the coronal plane correlated poorly with intraoperative findings and only minimally improved over the time course of the study.

Conclusion Proper assessment of a possible candidate for a rotator cuff repair should include an ultrasound with the tear size measured specifically in both the coronal and sagital planes.

Introduction: When subjected to strain or strain rates are higher than usual, the bone remodels to repair microdamage and to strengthen itself. During the initial resorption phase of remodeling, the bone is transitorily weakened and microdamage can accumulate leading to stress fracture.

Methods: To determine whether short –term suppression of bone turnover using bisphosphonates can prevent the initial loss of bone during the remodeling response to high bone strain and strain rates and potentially prevent stress fractures, we conducted a randomized, double blind, placebo-controlled trial of 324 new infantry recruits known to be at high risk for stress fracture. Recruits were given a loading dose of 30 mg of residronate or placebo daily for 10 doses during the first two weeks of basic training and then a once a week maintenance dose for following 12 weeks. Recruits were monitored by biweekly orthopedic examinations during 15 weeks of basic training for stress fractures. Bone scans for suspected tibial and femoral stress fractures and radiographs for suspected metatarsal stress fractures were used to verify stress fracture occurrence.

Results: By the intension to treat analysis and per protocol analysis, there was no statistically significant difference in the tibial, femoral, metatarsal, or total stress fracture incidence between the treatment group and the placebo.

Discussion: We conclude that prophylactic treatment with residronate in a training population at high risk for stress fracture using a maintenance dosage for the treatment of osteoporosis does not lower stress fracture risk.

Strains applied to bone can stimulate its development and adaptation. High strains and rates of strain are thought to be osteogenic, but the specific dose response relationship is not known. In vivo human strain measurements have been performed in the tibia to try to identify optimal bone strengthening exercises for this bone, but no measurements have been performed in the distal radial metaphysis, the most frequent site of osteoporotic fractures. Using a strain gauged bone staple, in vivo dorsal metaphyseal radial strains and rates of strain were measured in ten female patients during activities of daily living, standard exercises and falls on extended hands. Push-ups and falling resulted in the largest compression strains (median 1345 to 3146 με, equivalent to a 0.1345% to 0.3146% length change) and falling exercises in the largest strain rates (18 582 to 45 954 με/s). On the basis of their high strain and/or strain rates these or variations of these exercises may be appropriate for distal radial metaphyseal bone strengthening.

Mechanical loading during physical activity produces strains within bones. It is thought that these forces provide the stimulus for the adaptation of bone. Tibial strains and rates of strain were measured in vivo in six subjects during running, stationary bicycling, leg presses and stepping and were compared with those of walking, an activity which has been found to have only a minimal effect on bone mass.

Running had a statistically significant higher principal tension, compression and shear strain and strain rates than walking. Stationary bicycling had significantly lower tension and shear strains than walking. If bone strains and/or strain rates higher than walking are needed for tibial bone strengthening, then running is an effective strengthening exercise for tibial bone.

We studied the integrity of the rotator cuff in both dominant and non-dominant shoulders of 90 asymptomatic adults between the ages of 30 and 99 years using ultrasound. The criteria for diagnosis had been validated on unembalmed cadaver specimens. We found no statistically significant difference in the incidence of impingement findings between dominant and non-dominant arms or between genders. The prevalence of partial- or full-thickness tears increased markedly after 50 years of age: these were present in over 50% of dominant shoulders in the seventh decade and in 80% of subjects over 80 years of age. Our results indicate that rotator-cuff lesions are a natural correlate of ageing, and are often present with no clinical symptoms. Treatment should be based on clinical findings and not on the results of imaging.

We report four patients with unilateral postpartum sacroiliitis presenting with agonising unilateral pain, an elevated ESR, elevated alkaline phosphatase levels, leucocytosis and positive bone scans. The diagnosis of a non-infectious inflammatory cause was supported by the postpartum onset, the response to non-steroidal anti-inflammatory drugs, negative aspiration cultures in two cases and the lack of changes in the sacroiliac joints on long-term follow-up radiographs.

We report a prospective study of 783 male Israeli recruits aged from 17 to 26 years. The risk of stress fracture was inversely proportional to age on both univariate and multivariate analysis. Each year of increase of age above 17 years reduced the risk of stress fracture by 28%.

We have shown that stress fractures can be induced in the tibial diaphysis of an animal model by the repeated application of non-traumatic impulsive loads. The right hind limbs of 31 rabbits were loaded for three to nine weeks and changes in the bone were monitored by radiography and bone scintigraphy. The presence of stress fractures was confirmed histologically in some cases. Most animals sustained a stress fracture within six weeks and there was a positive correspondence between scintigraphic change and radiological evidence. Microscopic damage was evident at the sites of positive bone scans. The progression, location, and time of onset of stress fractures in this animal model were similar to those in clinical reports, making the model a useful one for the study of the aetiology of stress fractures.

A prospective study of 295 infantry recruits has shown that the mediolateral width of the tibia measured radiographically at each of three different levels in the bone had a statistically significant correlation with the total incidence of stress fractures as well as with those in the tibia alone or the femur alone. A narrow tibial width was shown to be a risk factor, but cortical thickness was not found to be significant.

Of 66 recruits who sustained stress fractures during basic training and returned to training after a period of rest, seven (10.6%) suffered recurrent fractures within one year. None of the recurrences was at the original anatomical site. All of the recruits with recurrent stress fractures had had at least one of their initial stress fractures in the femur. This suggests that a femoral stress fracture carries a high risk of recurrence at other sites.

In a prospective study of 295 male Israeli military recruits a 31% incidence of stress fractures was found. Eighty per cent of the fractures were in the tibial or femoral shaft, while only 8% occurred in the tarsus and metatarsus. Sixty-nine per cent of the femoral stress fractures were asymptomatic, but only 8% of those in the tibia. Even asymptomatic stress fractures do, however, need to be treated. Possible explanations for the unusually high incidence of stress fractures in this study are discussed.