Clinical manifestations of type IV ulna longitudinal dysplasia

PURPOSE

Ulna longitudinal dysplasia is an uncommon congenital anomaly that demonstrates a wide variety of clinical manifestations. The clinical manifestations and function of patients with Bayne type IV ulna longitudinal dysplasia have not been well characterized. The purpose of this study was to report the clinical features of type IV ulna longitudinal dysplasia and the extent to which this affects a patient's ability to perform activities of daily living.

METHODS

The medical records of children diagnosed with ulna longitudinal dysplasia in our institution between 1960 and 2004 were reviewed. The children found to have ulna longitudinal dysplasia with radiohumeral synostosis (Bayne type IV ulna dysplasia) were studied. The laterality of the deformity, associated musculoskeletal and nonmusculoskeletal anomalies, and treatments were recorded. Patients were interviewed regarding their ability to perform activities of daily living.

RESULTS

One hundred twenty-five patients with 146 affected limbs were identified with ulna dysplasia. Seventeen limbs in 14 patients (12% of affected limbs) demonstrated radiohumeral synostosis (RHS). Three of 14 patients with RHS had bilateral involvement. The elbows were fixed in 20 degrees to 90 degrees of flexion. No elbows were positioned in full extension. Eleven of the 17 involved limbs with RHS had digital anomalies. Nine of the 17 limbs had surgical reconstruction. The majority of these procedures were performed on the hand.

CONCLUSIONS

The elbow, forearm, wrist, and hand clinical findings associated with type IV ulna longitudinal dysplasia are variable. Surgical treatment usually focuses on correction of hand abnormalities. Many patients function satisfactorily and are able to perform daily activities without surgical intervention.

Intensive exercise may preserve bone mass of the upper limbs in spinal cord injured males but does not retard demineralisation of the lower body

STUDY DESIGN

Cross-sectional study comparing a group of active spinal cord injured (SCI) males carefully matched for age, height, and weight with active able-bodied male controls.

OBJECTIVES

To compare bone mass of the total body, upper and lower limbs, hip, and spine regions in active SCI and able-bodied individuals.

SETTING

Outpatient study undertaken in two centres in New Zealand.

METHODS

Dual energy X-ray absorptiometry (DEXA) scanning was used to determine bone mass. Questionnaires were used to ascertain total time spent in weekly physical activity for each individual. The criterion for entry into the study was regular participation in physical activity of more than 60 min per week, over and above that required for rehabilitation.

RESULTS

Seventeen SCI and their able-bodied controls met our required activity criterion. Bone mineral density (BMD) values of the total body and hip regions were significantly lower in the SCI group than in their controls (P=0.0001). Leg BMD and bone mineral content (BMC) were also significantly lower in the SCI group (P=0.0001). By contrast, lumbar spine BMD and arm BMD and BMC did not differ between the SCI and control groups. Arm BMD and BMC were greater (not significant) than the reference norms (LUNAR database) for both groups.

CONCLUSION

Intensive exercise regimens may contribute to preservation of arm bone mass in SCI males, but does not prevent demineralisation in the lower body.

Stress fractures of the upper extremity

Stress fractures are common injuries in the athletic population. Although much of the published literature has focused on lower extremity stress injuries, these injuries also occur in the upper extremities. Stress injuries of bone result from repetitive loads smaller than would be required to cause an acute fracture. As bone is repetitively stressed, it behaves like any solid substance. If deformity occurs within its elastic range, it returns to its original configuration. If stressed into its plastic range, permanent deformity occurs, and microfractures propagate, causing structural failure and complete fracture of the involved bone. High clinical suspicion is required for diagnosis because of historical and physical features can be vague. Plain radiographs are often inconclusive, but bone scans and MR imaging usually help elucidate the diagnosis. Most upper extremity stress injuries will heal with nonoperative management. In rare situations these injuries can progress to nonunion, which requires surgical correction.

Dynamic injury tolerances for long bones of the female upper extremity

This paper presents the dynamic injury tolerances for the female humerus and forearm derived from dynamic 3-point bending tests using 22 female cadaver upper extremities. Twelve female humeri were tested at an average strain rate of 3.7+/-1.3%/s. The strain rates were chosen to be representative of those observed during upper extremity interaction with frontal and side airbags. The average moment to failure when mass scaled for the 5th centile female was 128+/-19 Nm. Using data from the in situ strain gauges during the drop tests and geometric properties obtained from pretest CT scans, an average dynamic elastic modulus for the female humerus was found to be 24.4+/-3.9 GPa. The injury tolerance for the forearm was determined from 10 female forearms tested at an average strain rate of 3.94+/-2.0%/s. Using 3 matched forearm pairs, it was determined that the forearm is 21% stronger in the supinated position (92+/-5 Nm) versus the pronated position (75+/-7 Nm). Two distinct fracture patterns were seen for the pronated and supinated groups. In the supinated position the average difference in fracture time between the radius and ulna was a negligible 0.4+/-0.3 ms. However, the pronated tests yielded an average difference in fracture time of 3.6+/-1.2 ms, with the ulna breaking before the radius in every test. This trend implies that in the pronated position, the ulna and radius are loaded independently, while in the supinated position the ulna and radius are loaded together as a combined structure. To produce a conservative injury criterion, a total of 7 female forearms were tested in the pronated position, which resulted in the forearm injury criterion of 58+/-12 Nm when scaled for the 5th centile female. It is anticipated that these data will provide injury reference values for the female forearm during driver air bag loading, and the female humerus during side air bag loading.

Quantitative ultrasound of phalanges and dual-energy X-ray absorptiometry of forearm and hand in patients with end-stage renal failure treated with dialysis

The aim of the study was to evaluate the usefulness of quantitative ultrasound (QUS) measurement of the proximal phalanges of the hand in patients with end-stage renal failure (ESRF) treated with dialysis, and to compare results of this method with those from dual-energy X-ray absorptiometry (DXA) of hands and forearms (shaft and ultradistal site). Forty-one men aged 48.1 +/- 11.7 years and 31 women aged 43.1 +/- 12.3 years were examined. Mean QUS values of the hands in men and women with ESRF were significantly lower than the values of the healthy control group. There was a significant positive correlation between QUS and DXA of fingers, hands and also forearms, more pronounced in the shaft than in the ultradistal site. There was no significant difference in the measurements of extremities with or without a fistula. We conclude that QUS measurements are decreased in patients with ESRF treated with dialysis, and they correlate with DXA results. The simplicity of QUS makes it a valuable method in everyday practice. The clinical significance of the QUS results in these patients with ESRF treated with dialysis needs further investigation.