Tego Science, Inc.

There is growing interest in various biological supplements to improve tendon healing in patients after arthroscopic rotator cuff repair. The ideal biological supplement to strengthen rotator cuff remains unknown.

To assess the safety and efficacy of autologous cultured dermal fibroblast (ADF) injection on tendon-to-bone healing in patients after arthroscopic rotator cuff repair.

Case series; Level of evidence, 4.

Included were 6 patients who underwent arthroscopic rotator cuff repair between June 2018 and March 2020; all patients had a full-thickness rotator cuff tear (>2 cm) involving the supraspinatus and infraspinatus tendons. The patients were injected with ADF between the repaired tendon and footprint during arthroscopic rotator cuff repair using the suture bridge technique. The safety of ADFs and the procedure was evaluated at 5 weeks postoperatively, and the anatomical healing of the repaired tendon was accessed at 6 months postoperatively using magnetic resonance imaging and at 12 months using ultrasonography. Outcomes including shoulder range of motion (ROM), visual analog scale (VAS) for pain, and functional scores were measured at 6 and 12 months postoperatively.

Adverse reactions to ADF injection were not observed at 6 months after surgery. VAS and functional scores at 6 and 12 months postoperatively were significantly improved compared with preoperative scores (all P < .05). However, there was no significant difference on any ROM variable between preoperative and postoperative measurements at 6 and 12 months (all P > .05). No healing failure was found at 6 and 12 months postoperatively.

There was no adverse reaction to ADF injection, and all patients had successful healing after rotator cuff repair. A simple and easily accessible ADF injection may be a novel treatment option for increasing the healing capacity of torn rotator cuff tendons. Further clinical research is needed to verify the study results.

Myofibroblasts play a central role in matrix formation and wound contraction during wound healing and undergo apoptosis at the end of the healing. Hypertrophic scarring is a pathologic condition in which myofibroblasts persist in the tissue. It has been hypothesized that abnormalities in epidermal-dermal crosstalk underlie this pathology. Therefore, in this study, we investigated whether myofibroblasts are affected by keratinocytes. Transforming growth factor beta-induced myofibroblasts (Imyo) and myofibroblasts from hypertrophic scar tissue (Hmyo) were characterized using microarrays. Keratinocytes were co-cultured with myofibroblasts, and quantitative PCR analysis was performed. We found that numerous extracellular matrix- and smooth muscle cell-associated genes were upregulated in Imyo and Hmyo respectively, and these findings suggest that Hmyo are fully differentiated myofibroblasts and that Imyo are less differentiated than Hmyo. Decreased collagen type 1 gene expression was found in keratinocytes co-cultured with Imyo and Hmyo; further, α-smooth muscle actin expression in Imyo increased in the presence of keratinocytes. These observations indicate that keratinocytes play a role in the development of pathological fibrosis in hypertrophic scar tissue by regulating the behavior of dermal fibroblasts and myofibroblasts. We believe that this study provides the basis for understanding the pathophysiology of hypertrophic scarring and identifying new therapeutic approaches for this dysfunction.No Level Assigned This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors - www.springer.com/00266 .

For the treatment of wide scars, laser resurfacing procedures are generally used. However, sometimes their results are not satisfactory. Many clinical studies have reported that cultured epidermal allogenic sheets promote rapid and good quality wound healing. Therefore, the authors applied a cultured epidermal homograft (CEH) for scar management and investigated its outcomes.

Thirty-two patients who received a CEH (Kaloderm) after laser resurfacing (n = 14, under general anesthesia; n = 18, under local anesthesia) between February 2016 and June 2017 were enrolled. Patients treated with dermabrasion using laser resurfacing (n = 60) without CEH in the same period were used as controls. Clinical grading of the scars was performed using a Patient and Observer Scar Assessment Scale (POSAS) at postoperative 12 months.

The authors conducted a comparative analysis between the control and CEH groups. Evaluation based on Patient and Observer Scar Assessment Scale showed that the mean scores in control/CEH groups for the 7 observer components (vascularity, pigmentation, thickness, relief, pliability, surface area, and overall opinion) were 4.5/3.2, 3.3/2.8, 2.8/2.5, 3.6/3.5, 3.7/2.1, 2.3/1.9, and 3.2/2.7, respectively, with significant differences observed in vascularity, pliability, and surface area (Pvalues = 0.033, 0.021, and 0.048, respectively). Meanwhile, the mean scores in control/CEH groups for 7 patient components (pain, itching sense, color, stiffness, thickness, irregularity, and overall opinion) were 4.1/2.3, 3/3.1, 2.2/2.1, 2.2/1.7, 3.6/3.5, 1.8/1.5, and 2.2/1.9, respectively, with significant differences between groups observed in pain, stiffness, and overall opinion in the pairedttest (Pvalues = 0.041, 0.020, and 0.048, respectively).

Cultured epidermal homograft provided good quality wound healing and improved scar pliability. Cultured epidermal homograft left less scarring with no pain or other specific complications. Therefore, dermabrasion with CEH is useful for scar management.