Minimally invasive retrocalcaneal bursa pressure measurement: development and pilot application

Up to now diagnosis of Haglund's disease is based on patient's history and clinical findings. There is no valid diagnostic tool described to functionally detect retrocalcaneal bursitis. Retrocalcaneal bursa pressure may be increased in these patients. We hypothesized that retrocalcaneal bursa pressure can directly be measured. In this pilot investigation we tested the feasibility of a system which is already in clinical use for arterial blood pressure monitoring to quantitatively assess retrocalcaneal bursa pressure in a human and a swine cadaver specimen and in vivo. Using the presented system retrocalcaneal bursa pressure measurement is demonstrated to be feasible. Moreover, intrabursal pressure is reproducibly and validly quantified. In an uninjured subject increasing ankle dorsiflexion was not associated with increasing pressure in the retrocalcaneal bursa. Experimental liquid injection in the retrocalcaneal bursa was associated with increased intrabursal pressure and increasing pain. Feasibility of the tested setup could be proven. The question, if retrocalcaneal bursitis can be distinguished from further heel pathologies by different pressures in the retrocalcaneal bursa has to be addressed in a subsequent in vivo study.