Simple figure-of-eight bandaging is a widely employed practice following wing injury. Uses of wing bandaging include: immobilization before and after fracture repair, during wound management, and to protect the wing during transient nerve paralysis. Flighted pigeons were used to assess the impact of bandaging on soft and hard tissues in the pigeon wing, and the potential efficacy of ultrasound therapy in reversing these changes.
In two separate experiments presented here, ultrasound therapy was applied under standardized conditions (Forte USR ultrasound machine, Chattanooga Group, Inc., Hixson, TN, USA: probe = 2 cm diameter, scan rate = 4 cm/second, intensity = 0.1 W cm2, session duration = 3 minutes, duty cycle = 100%, coupling = room temperature ultrasound gel) for the prevention and correction of bandaging induced contractures and reduced range of motion of the carpal and elbow joints in pigeons. In a third experiment, bone loss during bandaging and during ultrasound therapy was evaluated.
Contracture development and reversal was assessed by applying a 0.5 kg weight to the outer two wing primaries with a Velcro cuff while the pigeons were in a standard measurement apparatus; angle measurements were taken once the wing was fully relaxed. A goniometer (loaded goniometry) was used to measure the angles of extension of the elbow (forward angle) and carpus (backward angle). Bone loss was determined by standardized serial measurements of metacarpals II-III employing an x-ray scanning bone densitometer.
The results from the first experiment indicated a highly significant (p≤0.0001) effect of 10 twice weekly ultrasound treatments, for the prevention of both bandaging-induced elbow and carpal rotation loss, starting at four days following the start of bandaging as compared to bandaged control wings. In the second experiment, pigeons that had one wing bandaged for 42 days, randomly assigned to either of two treatment groups, showed that even three twice weekly ultrasound treatments reversed the loss of wing rotation at the carpus significantly as compared to unbandaged controls (p=0.0014); although elbow rotation had not significantly changed with only three treatments, a trend was evident (p=0.14). In the final experiment, bone loss over 4 weeks of wing bandaging occurred at a rate of 2.96%/week, and bone density was significantly reduced (p=0.03) as compared to unbandaged control wings in the same birds; however, as expected, ultrasound therapy had no significant effect on bone loss during this same period.
Based on these preliminary investigations, therapeutic ultrasound was useful in the prevention and reversal of wing joint rotational loss seen in response to figure-of-eight wing bandaging, but did not reverse the bone loss trend toward disuse osteoporosis in these same birds. The potential therapeutic application of this treatment modality for a swifter return to normal soft tissue function and wing use after bandaging appears promising.