Scarring is the pathological phenomenon of the repair and reconstruction that happens after tissue damage and may affect the patient’s external appearance and physical function, causing deformity, disability and possibly a great psychological burden, especially when the scar is on the face. (1) Depressed scars develop as a result of scar contraction in all directions, especially at the base, with lack of adequate dermis and subcutaneous tissue in the region. Most studies have shown good results with autologous fat grafting in the treatment of depressed scars. However, there is paucity of literature addressing the peri-scar area and associated deformities and its correction. Around a depressed scar, there can be tethering, puckering, depression, loss of natural lines, colour and contour abnormalities and functional changes like disparity in facial animation. These problems need to be addressed for optimal cosmetic outcomes. For long-term scar management, most of the available medical and surgical therapies seem to be less effective in correcting peri-scar deformities. We found subcision of scar to address tethering, puckering and depression, along with fat grafting to address volume deficiency to be a useful modality, based upon the role of autologous fat cells as a “natural filler.” Its added role through adipose-derived stem cells (ADSCs) on improving scar quality cannot be overlooked, thus causing scar remodeling and long term cosmetic benefits. (2) Henceforth, we aimed to study the potential benefits of subcision with fat grafting on depressed scars as well as deformities in peri-scar area, to correct the ultimate deformity 3-dimensionally, as well as to study its role in improving the overall quality of scar.

The study performed was a prospective observational type of study. 10 patients with 11 depressed scars were included. It was conducted over a period of 2 years, from February 2023 to February 2025, in a single tertiary care centre. Patients above 12 years of age, having depressed scars of 1 year of duration or more, caused due to trauma or surgical intervention, and giving written informed consent were included. Scars due to any other etiology, patients with bleeding/ blood related disorders, immunocompromised (HIV/AIDS or malignancy), connective tissue disorders, and uncontrolled diabetes were excluded. METHODOLOGY: Preoperative evaluation: The peri-scar area was assessed in each patient, and marked for augmentation. Volume calculation was done according to the formula given. In cases with irregular or larger scars, the scar area was divided into multiple sections, and the volume of each section was calculated by the above-mentioned formula, and added to get the approximate total volume of fat graft required in the procedure. An additional 30% of the total volume calculated was added to get the final volume estimation needed for fat grafting (assuming that approximately 30% added volume would get absorbed in the post-operative period). (3) Calculation of pre-operative scores: 1.Score based on peri-scar deformity: This was added by us to assess the scars and surrounding area deformity, and plan treatment accordingly. 2.The Modified Vancouver Scar Scale: (4) 3.POSAS Patient Scale (POSAS 2.0): (5,6,7,8) 4. POSAS Observer Scale (POSAS 2.0): (5,6,7,8) 5.Scores based on additional parameters: We found that none of the above standardized scoring systems were addressing complete evaluation of the problems associated with our patients of depressed and puckered scars, as they were mostly focussing on hypertrophic scar assessment. Also, there was no standardized accepted scoring system available exclusively for depressed scar assessment. Hence, in order to understand depressed scars in a better way, we added certain scoring parameters in our study. (Table 1) Operative procedure: The procedure of micro fat grafting as given by Sydney Coleman was followed in this study in all cases: fat harvesting, refinement, and placement. (9,10) FAT HARVEST: The wetting solution consisted of 0.5% lidocaine and 1:2,00,000 adrenaline in Ringer’s lactate, infiltrated in the paraumbilical and infraumbilical abdominal wall adipose tissue, at a ratio of 1 ml of solution per cubic centimetre of fat graft to be harvested. After a waiting time of 5 minutes, the fat graft was harvested into Luer Lock syringes maintaining a low negative suction pressure. FAT REFINEMENT: The harvested fat was refined using centrifugation by the standard Coleman technique. After centrifugation, three layers were formed: the oil layer (upper level) was decanted and the aqueous layer (lower level) was drained out of the syringe. The middle layer, composed of predominantly fat graft, was separated to be used for the procedure. FAT PLACEMENT: (Figure 5) Subcision was performed prior to fat placement using 18G needle and blunt tip cannula, releasing all fibrous bands and tethering, and adequate space was created. The refined fat graft was transferred immediately to prevent air exposure. The fat graft was injected on withdrawal, depositing it in 0.1 cc aliquots to maximize surface area of contact with the surrounding tissue, in a cross-hatched pattern using long radial passes from multiple directions, followed by digital manipulation to flatten clumps and minor irregularities. The fat graft was injected in the space created below the scar by subcision, as well as in underlying deeper tissue. The end-point of fat placement was decided by the team of operating surgeons, based on the cosmetic correction and elevation of the depressed scar area achieved on table. The peri-scar area augmentation was done by injecting small aliquots of fat graft in the same manner, but without subcision, and in different layers below the dermis, to achieve satisfactory cosmetic improvement as compared to the normal unaffected side. Post-operative observations and monitoring: In the post-operative period, patients were observed for immediate changes like erythema, edema, tenderness, seroma/ hematoma formation, or fat embolism, and delayed complications like skin necrosis, surgical site infection, paraesthesia over the fat grafted area or donor site morbidity, if present, were noted. Follow up: The patients were followed up at the end of 1, 3 and 6 months for calculation of post-operative scores, as done pre-operatively.

The mean age of patients included was 28.36 years, with nearly equal representation of male (54.5%) and female (45.5%) patients. Most cases in the study (81.8%) had depressed scars of a time duration between 1-10 years. All the patients in this study presented with depressed scars of the head and neck region, with majority in the mid (45.5%) and lower (27.3%) face (cheek and mandibular region). There was nearly equal distribution in terms of scar etiology- post-traumatic (54.5%) and post-surgical scars (45.5%). The peri-scar area deformity-based score showed significant reduction in post-operative period at all follow up visits. This was also confirmed by calculation of volume deficit at depressed area post operatively at 6 months versus pre-operative status, indicating correction of depression at scar site as well as peri-scar area deformity correction and overall good results. The Modified Vancouver Scar Scale Score also showed a statistically significant difference compared to the preoperative scores at all follow up visits. The POSAS Patient Scale Score showed no significant reduction at 1 month follow up. But both the 3 and 6 months follow up scores showed a statistically significant reduction in their values compared to the preoperative scores. The POSAS Observer Scale Scores also showed a statistically significant reduction from their preoperative values at all follow up visits. The scores based on the psychosocial impact and societal burden due to the scar also showed significant reduction post-operatively at all follow up visits. The scores based on dysaesthesia/ paraesthesia and hypertrichois/ hypotrichosis due to the scar demonstrated no significant change.

In recent years, many studies have been done and shown good results with the use of autologous fat grafting for the treatment of various scars. However, there is paucity of literature addressing the peri-scar area and associated deformities and its correction. Around a depressed scar, there can be tethering, puckering, depression, loss of natural lines, colour and contour abnormalities and functional changes like disparity in facial animation, which need our attention in order to achieve optimal cosmetic outcomes. (14) Fat grafting techniques have been found successful in addressing few, if not all, of the problems associated with scars. But for long-term scar improvement and management, most of the available medical and surgical therapies seem to be less effective, especially in correcting peri-scar deformities. (15) We found subcision of the scar to address tethering, puckering and depression, and fat grafting to address volume deficiency to be a useful combination modality, based upon the role of autologous fat cells as a “natural filler.” The adipose-derived stem cells (ADSCs) present in fat grafts helped in further improvement in scar quality by remodeling, thus enhancing the long term cosmetic benefits. Various scoring systems have been used to evaluate the post-operative outcomes. A summary of the results of other studies compared with our study was made. Tables 2,3,4,5: Tables showing summary of comparison of our study with other studies on the basis of POSAS Scores. Study Preop POSAS-PS 6 months POSAS-PS p value Preop POSAS-OS 6 months POSAS-OS p value Present study 18.0 ± 4.66 10.45 ± 1.86 <0.001 (statistically significant) 20.42 ± 4.92 12.45 ± 2.76 <0.01 (statistically significant) Varghese et al (9) 5.75 ± 0.87 3.17 ± 1.12 <0.005 (statistically significant) 4.25 ± 1.42 2.58 ± 1.0 <0.005 (statistically significant) Study p value after comparing the POSAS-PS score at final follow up versus preoperative score p value after comparing the POSAS-OS score at final follow up versus preoperative score Present study p <0.001 (statistically significant) p <0.01 (statistically significant) Pallua et al (11) p <0.0001 (statistically significant) p = 0.0025 (statistically significant) Study Preop POSAS-PS 3 months POSAS-PS p value Preop POSAS-OS 3 months POSAS-OS p value Present study 18.0 ± 4.66 12.55 ± 2.54 <0.01 (statistically significant) 20.42 ± 4.92 14.33 ± 3.55 <0.01 (statistically significant) Jaspers et al (12) 5.1 ± 1.2 3.8 ± 1.6 <0.001 (statistically significant) 3.6 ± 0.9 2.9 ± 0.7 <0.001 (statistically significant) Study p value after comparing the POSAS-PS score at 6 months follow up versus preoperative score p value after comparing the POSAS-OS score at 6 months follow up versus preoperative score Present study p <0.001 (statistically significant) p <0.01 (statistically significant) Brown et al (13) p = 0.02 (statistically significant) p = 0.08 (not significant) None of the studies mentioned about their experience with peri-scar deformity. Our study aimed at highlighting this issue of peri-scar area deformity, and to develop a 3-dimensional approach for its correction using fat grafting, along with exploring the potential benefits of adipose-derived stem cells (ADSCs) in scar remodeling by comparing the pre- and post-operative POSAS and the Modified Vancouver Scar Scale Scores. Our study is unique in terms of incorporating our own parameters for scoring, because there is no ideal scoring system that addresses all problems associated with depressed scars. Most scoring systems are generalized or biased towards hypertrophic scars, which are not appropriate to draw conclusions based on them. Hence, there was a need for additional parameters to score depressed scar areas holistically. Parameters like psychosocial impact and societal burden due to scar, dysaesthesia/ paraesthesia at scar site and hypertrichosis/ hypotrichosis at scar site were also studied and we recorded significant changes, as these factors also affect patient satisfaction meaningfully. The volume deficit calculations done using a standard formula pre- and post-operatively guided us in re-confirming our results depicted in the improved scores. While doing the above study, we also felt the need of a standardized scar assessment scoring system exclusively made for analysis of depressed scars and peri-scar area deformity, that can be universally followed and used in such patients. This can revolutionize the way a plastic surgeon approaches these types of cases, helping us to assess the outcome and deliver superior cosmetic results with greater patient satisfaction.

Fat grafts have commonly been used as “natural fillers” for depressed scar correction. However, peri-scar area deformity gets ignored, causing sub-optimal results. A 3-D approach to correct a depressed scar and peri-scar area deformity using subcision and fat grafting can lead to more satisfactory cosmetic outcomes. Detailed and universally accepted scoring systems can further help in effectively dealing with these difficult cases.

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