Skin-derived fibroblasts for the treatment of refractory Achilles tendinosis: preliminary short-term results.

BACKGROUND Chronic Achilles tendinosis is a common musculoskeletal disorder often refractory to conservative management. Our study aimed to assess the safety and efficacy of the use of autologous skin-derived collagen-producing cells in the treatment of refractory Achilles tendinosis. METHODS We conducted a randomized, double-blind study on forty Achilles tendons in thirty-two patients (eight with bilateral involvement) who had a clinical and radiographic diagnosis of Achilles tendinosis. The patients ranged from twenty-two to sixty-seven years old and had a mean age of 45.2 years. The patients with unilateral involvement were randomized into the treatment group (twelve patients) and control group (twelve patients). The eight patients with bilateral involvement were individually randomized into treatment and control groups, with eight Achilles tendons in each group. Achilles tendons in the treatment group were injected under ultrasound guidance with laboratory-expanded, skin-derived fibroblasts suspended in autologous plasma. The control group received ultrasound-guided injection of a local anesthetic and physiotherapy. The Victorian Institute of Sport Assessment (VISA) questionnaire and visual analog scale (VAS) scores were used as the main outcome measures for both groups. RESULTS Significant differences in the mean VISA and VAS scores were detected between the treatment and the control groups for the patients with unilateral involvement at six months (p < 0.001 for both). With use of the Mann-Whitney U Test, significant differences in the VISA score were observed at the second visit and at the three-month and six-month visits (p = 0.02, p = 0.007, and p < 0.001 respectively). The VAS scores also showed significant differences at the second visit and at the six-month evaluation (p = 0.014 and p < 0.001, respectively). The eight patients with bilateral involvement were analyzed separately; with the number of patients studied, no significant differences in the VISA or VAS scores were observed between the treatment group and the control group. CONCLUSIONS These preliminary short-term results demonstrate that the injection of skin-derived fibroblasts for the treatment of Achilles tendinosis is safe. However, larger studies with a longer duration of follow-up are required to determine the long-term effectiveness before wider clinical application is considered.