Robot-assisted radial forearm free flap harvesting: A propensity score-matched case-control study

doi:10.21203/rs.3.rs-1617775/v1

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Robot-assisted radial forearm free flap harvesting: A propensity score-matched case-control study

https://doi.org/10.21203/rs.3.rs-1617775/v1

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published 05 Feb, 2023

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Although some surgeons prefer anterolateral thigh and latissimus dorsi flap for soft tissue reconstruction in head and neck area because it minimizes donor site complications, radial forearm flap remains the workhorse for soft tissue reconstruction due to its reliability. To reduce donor site morbidity, the authors developed a novel technique for radial forearm flap harvesting using a robotic device.

42 radial forearm free flap reconstruction cases were studied, consisting of 31 conventional and 11 robot-assisted cases. 1:1 propensity score matching was done according to age, sex, previous and postoperative radiation therapy history and method used for vein anastomosis.

There were no significant difference was in flap outcome, which was 100% vitality in the robot-assisted group and 90.9% vitality in the conventional group. The robot-assisted group showed significantly longer mean harvesting time than did the conventional group, being 107.2 minutes and 67.0 minutes respectively.

Robot-assisted radial forearm flap harvesting can reduce donor site complications by minimizing incision. When more surgical experience is gained under appropriate case selection, we expect our robot-assisted method will yield a harvesting time similar to that of the conventional method and thus become more reliable and feasible.

Robot-assisted radial forearm flap

Robot-assisted flap harvesting

Robot-assisted soft tissue reconstruction

Robot-assisted head and neck surgery

Radial forearm free flap has been the workhorse flap in head and neck reconstruction since Yang et al. reported it in 1981 [1]. It is a fasciocutaneous flap with a major vascular trunk based on the radial artery. Abundant blood flow can be supplied to the skin paddle of the flap via several septocutaneous perforators, allowing harvesting of large skin paddles [2]. Radial forearm free flap has definite advantages in head and neck reconstruction due to its superior flexibility and pliability. Moreover, the large diameter and long pedicle length of the vessel makes vascular anastomosis easier and more reliable.

Despite this reliability and versatility, radial forearm free flap conveys shortcomings such as long linear scar with wide area of altered skin texture, and possible complications such as altered sensation and decreased range of motion [3,4]. Various attempts have been made to minimize such shortcomings. While full or split thickness skin graft is widely used to cover skin paddle defects, attempts with local flap and autologous fat transplantation have been tried, with favorable results [5, 6, 7]. Endoscopic-assisted pedicle dissection has been utilized to reduce linear scarring for harvesting vascular pedicle [8].

Due to its reliability and usefulness, robot-assisted surgery in head and neck area has recently come into wide use not only in tumor ablation but also in flap harvesting [9, 10]. Compared to endoscopic-assisted flap harvesting, robot-assisted surgery allows 3-dimensional and higher resolution viewing. Various instruments, including electrocautery devices, provide greater flexibility and thus more precise manipulation [11].

To our knowledge, there have been no trials or reports on robot-assisted radial forearm free flap harvesting. One study reported that endoscopic-assisted radial forearm free flap harvesting reduced the linear scar from pedicle dissection, yielding more aesthetic results and reducing donor site discomfort [8]. Robot-assisted surgery, being more technically advanced than endoscopic-assisted surgery, lowers the entry barrier to radial forearm free flap harvesting and entails less donor site morbidity due to the reduction in linear scarring. The aim of our study is to compare cases of robot-assisted harvesting with conventional harvesting of radial forearm free flap under case control using propensity score matching in order to compare the safety and efficacy of each approach.

Case selection

Table 1. Case selection

42 cases of radial forearm free flap reconstruction done in a single institute by a single surgeon between October 2018 and July 2021 were selected. 31 cases of flap harvesting were done conventionally and 11 cases were robot-assisted. Patients were informed about the merits and disadvantages of each method and given a choice of surgical procedure. In order to minimize the effects of other factors on flap vitality aside from method of surgery, 1:1 propensity score matching was done. Age, sex, previous and postoperative radiation therapy history and method used for vein anastomosis were used as the criteria. Finally, 22 cases, 11 from each group, were included (Table 1).

Evaluation of surgical method

Flap survival rates were compared to assess the overall outcome of surgery. Harvesting times were compared to evaluate difficulty and efficacy of surgery. Statistical analysis was done by IBM SPSS Statistics for Windows, version 26 (IBM Corp., Armonk, N.Y., USA).

Robot-assisted harvesting procedure

A DaVinci Si robot was used for robot-assisted radial forearm free flap harvesting (Fig 1). To minimize postoperative bleeding, harvesting was done without tourniquet. After the flap was designed, the radial artery path was identified by palpation of the pulse. Next, flexor carpi radialis and palmaris longus tendons, which must be preserved for hand movement, were marked. A skin paddle was designed according to the defect size, and the vascular pedicle, including cephalic vein, was dissected as usual. After raising the skin paddle, an additional 2 cm of skin was dissected without conventional linear incision to make space for the retractor and robotic devices. When the retractor was successfully positioned, careful dissection and ligation of pedicle was done with robotic devices and the flap completely harvested.

After flap harvesting, essential insetting with key suture was done. Under microscopy, end-to-end artery anastomosis was done with 9-0 nylon and end-to-end vein anastomosis was done with a 9-0 nylon suture or GEM coupler (Synovis Micro Companies Alliance, Inc, Birmingham, AL, USA). Donor site repair was done with split thickness skin graft from thigh with dermatome and negative pressure wound therapy was applied to protect and accelerate donor site healing.

Demographics

Total 22 cases, consisting of 11 cases of robot-assisted harvesting and 11 cases of conventional harvesting with propensity score matching, were reviewed. Among these, the tongue was the most common defect site at 45.5% and 54.5% respectively. Due to the case control with propensity score matching, demographics of the cases generally showed no statistical difference although in robot-assisted harvesting cases, the mean age was 47.2, lower than that of conventional cases, 55.7 (Table 2).

Table 2. Case information

Flap parameters

To compare flaps, mean surface area, artery and vein used in neck, and veins of the flap were studied. There was no statistical difference in mean surface area between robot and conventional groups. In both groups, the superior thyroid artery was the most common artery used in neck, being 54.5% and 63.6% in robot and conventional groups, respectively. In both groups, facial vein was most frequently used in neck, being 90.9% and 81.8% in robot and conventional groups. Harvested flap in both groups included vena comitans. The portion of cephalic vein harvested was 54.5% in the robot group and 63.6% in the conventional group, with no statistical difference (Table 3).

Table 3. Flap parameters & outcome

Outcome comparison

To compare outcome and reliability of robot-assisted and conventional harvesting, the flap survival rate was evaluated and found to be 100% in the robot group and 90.9% in the conventional group, showing no statistical difference (Table 3).

Harvesting time comparison was done to evaluate efficacy of robot-assisted harvesting. Mean harvesting time was 107.2 minutes in the robot group and 67 minutes in the conventional group, showing statistical difference (Table 3).

Postoperative healing

During postoperative follow-up, robot cases showed more satisfying aesthetic results due to linear scar reduction (Fig 2).

Some surgeons prefer anterolateral thigh and latissimus dorsi flaps over radial forearm flap for soft tissue reconstruction in head and neck area because donor site repair can be done by primary closure[12]. Also, it is thought that younger patients who are sensitive to aesthetic outcome will prefer anterolateral thigh flap because the scar can be hidden [13]. In our study, however, some patients who were sensitive to cosmetic results preferred robot-assisted radial forearm flap to anterolateral thigh flap, presumably because the scar of anterolateral thigh flap is much longer than that of radial forearm flap and due to thigh asymmetry caused by large volumetric defect after anterolateral thigh flap. This may also account for the significantly younger mean age of the robot-assisted radial forearm flap group.

Many studies reported methods of repairing donor site after radial forearm flap. Usually split thickness and full thickness skin grafts are used for repair [14, 15]. Recently, local flap or allogenic dermal matrix is being used because skin grafts require an additional donor site such as thigh or abdomen. Potet et al. reported primary closure of the donor site by local flap (“keystone flap”), [6] and Nam et al. reported using an allogenic dermal matrix to repair the donor site [16]. Recently, endoscopic-assisted radial forearm flap harvesting has been tried, Van Kouwenberg et al. reporting that it reduced linear scar length. This resulted in decreased donor site complications compared to conventional cases, such as numbness, graft loss, hypertrophic scarring, delayed wound healing, tendon exposure and complex regional pain syndrome. Moreover, based on patient surveys after surgery, cosmetic outcomes were better. Finally, functional scoring of such factors as overall discomfort, strength, flexibility, and cold sensitivity was higher [8].

In our study, the mean flap survival rate was 100% in the robot group and 90.9% in the conventional group. The mean survival rate was higher in the robot group but without statistical difference. Mean flap harvesting time was 107.2 minutes in the robot group and 67 minutes in the conventional group. Mean flap harvesting time was higher in the robot group, with statistical difference.

Table 2. Robot-assisted group harvesting time

Flap harvesting times for all robot-assisted cases were reviewed (Table 4). As experience increased, harvesting time showed a decreasing tendency. 3 of 4 recent cases showed 80-90 minutes, 10 to 20 minutes longer than the mean time for the conventional group, within the standard deviation range. There is also a learning curve for most kinds of surgeries. Many studies have reported a learning curve in robot-assisted surgery, which requires mastering device manipulation and 3-dimensional magnified viewing. Sanjeev K. et al reported that even experienced surgeons who had performed more than 1000 open prostatectomies underwent a learning curve when performing robot-assisted surgery. Overall surgery time showed a decreasing tendency until 50 cases experience and after 100 cases experience, overall surgery time showed a narrow distribution [17]. Koh et al reported mean overall surgery time of 40 to 50 cases experience was 29% lower than that of the first 10 cases [18]. We expect robotic flap harvesting time to decrease to a level similar to that of the conventional group after prolonged experience.

Robot-assisted surgery is technically more advanced than endoscopic-assisted surgery. Robotic devices provide magnified 3-dimensional images with a much higher resolution compared to endoscopic devices. While performing endoscopic-assisted surgery, a surgeon has to use long-shank hand instruments, which require caution due to their high sensitivity. However, robotic arms can freely connect and disconnect several robotic instruments such as Metzenbaum scissors, vascular clamps, and energy devices, allowing a surgeon to manipulate multiple instruments simultaneously. Furthermore, robotic arms are flexible and precise, allowing accurate manipulation free from physical barriers. These technical advances increase ease and accuracy of some kinds of surgery compared to the use of endoscopic devices.

Ease of flap harvesting, low rates of vascular anatomical variation, and adequate length and diameter of pedicle are the main advantages of radial forearm free flap. Adequate subcutaneous tissue thickness in forearm area provides better pliability, yielding good functional results after reconstruction. In case sensory reconstruction is needed, lateral cutaneous nerve can be included in reconstruction. Finally, overall surgery time can be reduced using the two-team approach.

Based on our study and earlier literature findings, robot-assisted radial forearm free flap harvesting shows better aesthetic outcome by avoiding long linear scar for pedicle dissection. Compared to endoscopic-assisted radial forearm free flap harvesting, technical robotic advances such as higher resolution, 3-dimensional viewing and precise device manipulation can allow the surgeons to more easily harvest flap without linear incision. When used appropriately, robot-assisted radial forearm free flap harvesting will increase patient satisfaction with aesthetics and functional outcome without any difference in surgical outcome such as flap survival rate.

This is an observational study. Ethics Review Board of Yonsei University Dental Hospital Institutional Review Board has confirmed that no ethical approval is required.

Funding Declaration

This research received no specific grant from any funding agency in the public, commercial, or not-for-profit sectors

Competing interests

Author Seung-Woo Shin, Author Hyounmin Kim, Author Woong Nam, Author Hyung Jun Kim, Author In-Ho Cha, Author Yoon Woo Koh, Author Dongwook Kim declare that they have no conflict of interest.

Yang, G. (1981). Forearm free skin flap transplantation; report of 56 cases. National Medical Journal of China. Med. J. China, 61, 139.
de Chardon, V. M., Balaguer, T., Chignon-Sicard, B., Riah, Y., Ihrai, T., Dannan, E., & Lebreton, E. (2009). The radial forearm free flap: a review of microsurgical options. Journal of plastic, reconstructive & aesthetic surgery, 62(1), 5-10..
Selvaggi, G., Monstrey, S., Hoebeke, P., Ceulemans, P., Van Landuyt, K., Hamdi, M., ... & Blondeel, P. (2006). Donor-site morbidity of the radial forearm free flap after 125 phalloplasties in gender identity disorder. Plastic and reconstructive surgery, 118(5), 1171-1177.
Kovar, A., Choi, S., & Iorio, M. L. (2019). Donor site morbidity in phalloplasty reconstructions: outcomes of the radial forearm free flap. Plastic and Reconstructive Surgery Global Open, 7(9).
Peters, F., Smit, N., Möhlhenrich, S. C., Bock, A., Kniha, K., Raith, S., ... & Modabber, A. (2021). Objective and Subjective Comparisons of Split Thickness Skin Graft and Full Thickness Skin Graft for Radial Forearm Flap Donor Sites Using a New Measuring Method. Journal of Craniofacial Surgery, 32(6), e594-e598.
Potet, P., De Bonnecaze, G., Chabrillac, E., Dupret‐Bories, A., Vergez, S., & Chaput, B. (2020). Closure of radial forearm free flap donor site: A comparative study between keystone flap and skin graft. Head & Neck, 42(2), 217-223.
Longo, B., Sorotos, M., Laporta, R., & Santanelli di Pompeo, F. (2019). Aesthetic improvements of radial forearm flap donor site by autologous fat transplantation. Journal of plastic surgery and hand surgery, 53(1), 51-55.
Van Kouwenberg, E. A., Yan, A., Patel, A., McLaughlin, R. L., Northrup, P., Cintron, M., & Agag, R. L. (2019). Endoscopic-assisted radial forearm free flap harvest: a novel technique to reduce donor site morbidity. Journal of Reconstructive Microsurgery, 35(01), 022-030.
Lira, R. B., Chulam, T. C., de Carvalho, G. B., Schreuder, W. H., Koh, Y. W., Choi, E. C., & Kowalski, L. P. (2018). Retroauricular endoscopic and robotic versus conventional neck dissection for oral cancer. Journal of Robotic Surgery, 12(1), 117-129.
Fouarge, A., & Cuylits, N. (2020). From open to robotic-assisted latissimus dorsi muscle flap harvest. Plastic and Reconstructive Surgery Global Open, 8(1).
Chung, J. H., You, H. J., Kim, H. S., Lee, B. I., Park, S. H., & Yoon, E. S. (2015). A novel technique for robot assisted latissimus dorsi flap harvest. Journal of Plastic, Reconstructive & Aesthetic Surgery, 68(7), 966-972.
Niu, Z., Chen, Y., Li, Y., Tao, R., Lei, Y., Guo, L., ... & Han, Y. (2021). Comparison of Donor Site Morbidity Between Anterolateral Thigh and Radial Forearm Free Flaps for Head and Neck Reconstruction: A Systematic Review and Meta-Analysis. Journal of Craniofacial Surgery, 32(5), 1706-1711.
Oranges, C. M., Ling, B., Tremp, M., Wettstein, R., Kalbermatten, D. F., & Schaefer, D. J. (2018). Comparison of anterolateral thigh and radial forearm free flaps in head and neck reconstruction. in vivo, 32(4), 893-897.
Gaukroger, M. C., Langdon, J. D., Whear, N. M., & Zaki, G. A. (1994). Repair of the radial forearm flap donor site with a full-thickness graft. International journal of oral and maxillofacial surgery, 23(4), 205-208.
Davis III, W. J., Wu, C., Sieber, D., & Vandevender, D. K. (2011). A comparison of full and split thickness skin grafts in radial forearm donor sites. Journal of hand and microsurgery, 3(01), 18-24.
Kim, J. Y., Kim, Y. K., Lee, S., & Nam, W. (2018). Minimization of Radial Forearm Flap Donor-Site Scar Using Endoscopy and Allogeneic Dermal Matrix. Journal of Oral and Maxillofacial Surgery, 76(8), 1825-e1.
Kaul, S., Shah, N. L., & Menon, M. (2006). Learning curve using robotic surgery. Current urology reports, 7(2), 125-129.
Kim, W. S., Ban, M. J., Chang, J. W., Byeon, H. K., Kim, H., Han, J. H., ... & Choi, E. C. (2014). Learning curve for robot-assisted neck dissection in head and neck cancer: a 3-year prospective case study and analysis. JAMA Otolaryngology–Head & Neck Surgery, 140(12), 1191-1197.

Table 4 is not available with this version.

No competing interests reported.

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Editorial decision: Major revision
01 Jan, 2023
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Reviewers agreed at journal
17 Oct, 2022
Reviewers agreed at journal
15 Sep, 2022
Reviewers invited by journal
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Editor assigned by journal
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Submission checks completed at journal
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Robot-assisted radial forearm free flap harvesting: A propensity score-matched case-control study

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