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Original Article  |  Open Access  |  11 Jan 2023

Treatment of recurrent carpal tunnel syndrome with fat grafting as an adjunct

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Plast Aesthet Res 2023;10:1.
10.20517/2347-9264.2022.30 |  © The Author(s) 2023.
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Aim: The purpose of this study is to compare the surgical outcomes of treating recurrent carpal tunnel with recurrent carpal tunnel release only compared to recurrent carpal tunnel release with fat grafting as an adjunct.

Methods: Retrospective case-control study was performed of the recurrent carpal tunnels treated, excluding explicit nerve injury such as transections, neuromas in continuity, etc. Patients with recurrent carpal tunnel received re-release of carpal tunnel only or fat grafting as an adjunct. The outcomes of both groups were compared utilizing chi-square analysis.

Results: A total number of 81 patients were found to meet the inclusion criteria. Of the recurrences, a total of 16 patients did not receive fat grafting and 65 did. The rate of improvement in symptoms for performing a carpal tunnel release was only 50.0% and for performing carpal tunnel release with fat grafting was 92%, with P-value < 0.00.

Conclusion: Adipose-derived stem cells as an adjunct to carpal tunnel release increased the rate of improvement in symptoms of carpal tunnel compression after recurrence compared to carpal tunnel release alone. Further studies need to be performed to confirm the validity of these findings.


Carpal tunnel surgery, fat grafting, peripheral nerve


Carpal tunnel surgery is one of the most common hand operations performed today[1]. Within these cases, the incidence of recurrent carpal tunnel ranges from 1% to 31%, with only about 5% of the reported cases undergoing surgery[2]. There are various reports in the literature regarding the best procedure for these recurrent cases, including extensive external and internal neurolysis, various flap techniques, venous wrapping, and prosthetic implants[2]. Unfortunately, the literature does not include any comparative studies that could conclude the best management of these patients. The main principles in revision surgery that have been advocated include the addition of vascularized tissues to help nerves heal, adequate removal of scarring around the nerve, and maintenance of adequate nerve gliding[3-5]. One of the most novel methods includes adding adipose derive stem cells as an adjunct to recurrent carpal tunnel release, yet the literature includes small and contradictory reports[6,7].

Fat grafting is a method to deliver adipose-derived stem cells to the median nerve during carpal tunnel release. Stem cell therapy’s effect on nerve regeneration has been studied extensively in the basic science literature. Adipose-derived stem cells are the most practical as they can be harvested easily from patients with a high yield of stem cells, about one million stem cells per gram of fat[8,9]. The mechanisms proposed in which adipose-derived stem cells aid in peripheral nerve injuries are: in situ differentiation to Schwann cells and secretion of trophic and anti-inflammatory factors[10-15,16-20]. The studies demonstrate that the positive effects of adipose-derived stem cells on peripheral nerve regeneration are mostly limited to animal models[21].

There have been many studies using adipose-derived stem cells as a surgical treatment for nerve pain, and the results are encouraging[19]. Stromal vascular fraction was used to treat erectile dysfunction in 47% of patients after radical prostatectomy[22]. In a randomized controlled trial, patients with post-mastectomy pain treated with fat grafting had an average pain reduction of 54.9% and also improved health-related quality of life measurements[23]. Among patients with neuropathic pain after burn injury, 6 out of 7 patients treated with fat grafting had reduced pain and thus reduced consumption of pain medication[24].

In this study, we compare two modalities to treat recurrent carpal tunnel: (1) recurrent carpal tunnel release only; and (2) recurrent carpal tunnel release with fat grafting. The goal is to assess subsequent improvement in carpal tunnel syndrome using each method.


The retrospective review of data was approved by Dartmouth Hitchcock Medical Center Institutional Review Board, IRB# 020000917. All carpal tunnel surgeries performed by one surgeon, Dr. Joseph Rosen, between July 2011 to October 2021 were reviewed. A recurrence of carpal tunnel syndrome was primarily defined by clinical symptoms, the physical examination, electrical studies and willingness to undergo surgery. Patients with nerve injury, transections, neuromas in continuity, etc., were excluded. All patients underwent a nerve conduction study that ruled out other pathology, and about 88% of the patients in this study had records that could be reviewed.

For all cases, patients underwent general anesthesia due to the need to harvest fat from the abdomen. The recurrent carpal tunnel was treated with an open approach. The fat was harvested exclusively from the abdomen using Coleman cannulas and purified with the Puregraft system and washed with lactated ringer’s solution. The fat was injected around the median nerve without damaging the nerve. Post-operatively, patients were not splinted and were encouraged to become physically active as soon as tolerated. Patient follow-up appointment notes were reviewed and evaluated for symptoms and discussion of treatment options, including re-operation. The study groups were compared utilizing a t-test, setting significance at P < 0.05.


In this review, the recurrent carpal tunnels treated thus far, excluding explicit nerve injury such as transections, neuromas in continuity, etc., totaled 81 cases. Statistical comparison between demographic variables demonstrated no statistical differences [Table 1]. About 80% of the patient had motor latencies 4.2 ms or absent at the wrist and 68% had sensory latencies 3.6 ms or absent at the wrist. The rate of improving symptoms for performing a carpal tunnel release was only 50.0% and for performing carpal tunnel release with fat grafting was 92%, the Pearson χ2 was 17.1, and P-value < 0.00 [Table 2]. The average amount of grafted fat injected into the wrist was about 5.4 ± 3.8 mL. On average, patients presented with an initial recurrence at about 6.25 ± 0.91 years after their initial surgery. Patients were followed for an average of 1.4 ± 0.2 years after revision surgery. Improvement in symptoms was defined as improvement in clinical symptoms and no further scheduled or performed surgery.

Table 1

Demographics of participants in the study

SCTR onlySCTR + Fat graftingP-value
Age (mean)57550.542
Male (%)50550.737
Right (%)69550.332
Diabetes (%)38290.521
Motor Latency (mean)
Table 2

Outcome of the treatments of recurrent carpal tunnel

No improvement in symptomsImprovement in symptoms
SCTR only50.0%50.0%
SCTR + Fat grafting8%92%

In terms of complications, we had one case of cellulitis and another patient presented with significant pain in the abdomen after surgery, a computerized tomography (CT) scan showed no abnormal pathology and the patient recovered.


Fat grafting as an adjunct to recurrent carpal tunnel surgery has been reported by various case series in 2000 and later in 2015[8,9]. The initial study demonstrated no difference in adding fat grafting and the latter demonstrated a dramatic improvement. Our study is larger in scope and followed for a longer period and fat grafting as an adjunct to treatment continued to improve outcomes for patients. Similar to previous studies, recurrent carpal tunnel release continued to improve symptoms in about 50% of patients.

The suspected mechanism of action is the differentiation of adipocyte-derived stem cells into Schwann cells and the release of trophic and anti-inflammatory factors[10-15]. These studies are based on work on animal models of nerve injury, yet there is no study correlating these hypotheses to the actual improvement in clinical studies.

One of the difficulties of these cases is the definition of recurrent carpal tunnel. Patients present with similar symptoms as before and sometimes after a period of improvement. Test such as electrical studies does not always correlate with symptomatology, about 25% of patient in this study demonstrated clinical symptoms without positive electrical studies[25]. In this study, it was general clinical symptomatology and physical exam presentation that prompted offering the patient further treatment. There is also a heterogenous assortment of techniques of the original carpal tunnel release, including endoscopic carpal tunnel release. The overwhelming majority of the recurrent carpal tunnel patients came from external referrals; therefore, the data is incomplete regarding the initial presentation of symptoms and overall evaluation. Even though these factors make the data less “clean” in terms of making statistical conclusions, it is the reality presented in the clinic for hand surgeons.

This initial data demonstrate a positive experience utilizing fat grafting as an adjunct to recurrent carpal tunnel release. There are gaps in the data, for example, the first recurrence is about 6 years after the first surgery, while the data provided only involve more than one year of follow-up. At this time, there is a statistically significant difference in the outcomes between the two groups, and these differences may disappear over time. The clinical symptomatology, including numbness and tingling, loss of sensation, muscle weakness, Phalen’s sign and Tinnel’s sign, was present in all cases, but improvement in symptoms was inconsistently documented and a detailed comparison could not be provided; overall, the patient’s symptoms improved. This study provides preliminary data that a simple adjunct can improve outcomes; therefore, we consider it worthy of further evaluation with a randomized controlled trial.



We would like to thank the Department of Surgery at Dartmouth Hitchcock Medical Center for their continued support.

Authors’ contributions

Made substantial contributions to conception and design of the study and performed data analysis and interpretation: Rosen J, Cabrejo R

Performed data acquisition and provided administrative, technical, and material support: Rosen J, Cabrejo R, Podsednik A

Availability of data and materials

Not applicable.

Financial support and sponsorship


Conflicts of interest

All authors declared that there are no conflicts of interest.

Ethical approval and consent to participate

The retrospective review of data was approved by Dartmouth Hitchcock Medical Center Institutional Review Board, IRB#020000917.

Consent for publication

Not applicable.


© The Author(s) 2023.


1. Fajardo M, Kim SH, Szabo RM. Incidence of carpal tunnel release: trends and implications within the United States ambulatory care setting. J Hand Surg Am 2012;37:1599-605.

2. Soltani AM, Allan BJ, Best MJ, Mir HS, Panthaki ZJ. A systematic review of the literature on the outcomes of treatment for recurrent and persistent carpal tunnel syndrome. Plast Reconstr Surg 2013;132:114-21.

3. Duclos L, Sokolow C. Management of true recurrent carpal tunnel syndrome: Is it worthwhile to bring vascularized tissue? Chir Main 1998;17:113-7, discussion 118.

4. Reisman NR, Dellon AL. The abductor digiti minimi muscle flap: a salvage technique for palmar wrist pain. Plast Reconstr Surg 1983;72:859-65.

5. Jones NF, Ahn HC, Eo S. Revision surgery for persistent and recurrent carpal tunnel syndrome and for failed carpal tunnel release. Plast Reconstr Surg 2012;129:683-92.

6. Impelmans B, Miles J, Burke F. The use of free fat grafts in recalcitrant carpal tunnel: a retrospective study. Eur J Plast Surg 2001;24:12-7.

7. Krześniak NE, Noszczyk BH. Autologous fat transfer in secondary carpal tunnel release. Plast Reconstr Surg Glob Open 2015;3:e401.

8. Tsuji W, Rubin JP, Marra KG. Adipose-derived stem cells: implications in tissue regeneration. World J Stem Cells 2014;6:312-21.

9. Kern S, Eichler H, Stoeve J, Klüter H, Bieback K. Comparative analysis of mesenchymal stem cells from bone marrow, umbilical cord blood, or adipose tissue. Stem Cells 2006;24:1294-301.

10. Kingham PJ, Kalbermatten DF, Mahay D, Armstrong SJ, Wiberg M, Terenghi G. Adipose-derived stem cells differentiate into a Schwann cell phenotype and promote neurite outgrowth in vitro. Exp Neurol 2007;207:267-74.

11. Orbay H, Uysal AC, Hyakusoku H, Mizuno H. Differentiated and undifferentiated adipose-derived stem cells improve function in rats with peripheral nerve gaps. J Plast Reconstr Aesthet Surg 2012;65:657-64.

12. Abbas OL, Borman H, Uysal ÇA, Gönen ZB, Aydin L, Helvacioğlu F, Ilhan Ş, Yazici AC. Adipose-derived stem cells enhance axonal regeneration through cross-facial nerve grafting in a rat model of facial paralysis. Plast Reconstr Surg 2016;138:387-96.

13. Erba P, Mantovani C, Kalbermatten DF, Pierer G, Terenghi G, Kingham PJ. Regeneration potential and survival of transplanted undifferentiated adipose tissue-derived stem cells in peripheral nerve conduits. J Plast Reconstr Aesthet Surg 2010;63:e811-7.

14. Suganuma S, Tada K, Hayashi K, Takeuchi A, Sugimoto N, Ikeda K, Tsuchiya H. Uncultured adipose-derived regenerative cells promote peripheral nerve regeneration. J Orthop Sci 2013;18:145-51.

15. Hsieh SC, Chang CJ, Cheng WT, Tseng TC, Hsu SH. Effect of an epineurial-like biohybrid nerve conduit on nerve regeneration. Cell Transplant 2016;25:559-74.

16. Piñal F. Outcomes of carpal tunnel release in complex regional pain syndrome/reflex sympathetic dystrophy/sudeck disease patients. Plast Reconstr Surg 2022;150:93-101.

17. Wei Z, Fei Y, Su W, Chen G. Emerging role of schwann cells in neuropathic pain: receptors, glial mediators and myelination. Front Cell Neurosci 2019;13:116.

18. Ersen B, Kahveci R, Uğraş N, Ocakoğlu G. Evaluation of the effects of fat graft wrapping on early nerve regeneration: an experimental study. Turkiye Klinikleri J Med Sci 2018;38:303-8.

19. Kubiak CA, Kung TA, Brown DL, Cederna PS, Kemp SWP. State-of-the-art techniques in treating peripheral nerve injury. Plast Reconstr Surg 2018;141:702-10.

20. Watanabe Y, Sasaki R, Matsumine H, Yamato M, Okano T. Undifferentiated and differentiated adipose-derived stem cells improve nerve regeneration in a rat model of facial nerve defect. J Tissue Eng Regen Med 2017;11:362-74.

21. Zhang R, Rosen JM. The role of undifferentiated adipose-derived stem cells in peripheral nerve repair. Neural Regen Res 2018;13:757-63.

22. Elgammal YM, Zahran MA, Abdelsalam MM. A new strategy for the early detection of alzheimer disease stages using multifractal geometry analysis based on K-Nearest Neighbor algorithm. Sci Rep 2022:12.

23. Juhl AA, Karlsson P, Damsgaard TE. Fat grafting for alleviating persistent pain after breast cancer treatment: a randomized controlled trial. J Plast Reconstr Aesthet Surg 2016;69:1192-202.

24. Fredman R, Edkins RE, Hultman CS. Fat grafting for neuropathic pain after severe burns. Ann Plast Surg 2016;76 Suppl 4:S298-303.

25. Witt JC, Hentz JG, Stevens JC. Carpal tunnel syndrome with normal nerve conduction studies. Muscle Nerve 2004;29:515-22.

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OAE Style

Cabrejo R, Podsednik A, Rosen J. Treatment of recurrent carpal tunnel syndrome with fat grafting as an adjunct. Plast Aesthet Res 2023;10:1.

AMA Style

Cabrejo R, Podsednik A, Rosen J. Treatment of recurrent carpal tunnel syndrome with fat grafting as an adjunct. Plastic and Aesthetic Research. 2023; 10(1): 1.

Chicago/Turabian Style

Raysa Cabrejo, Alison Podsednik, Joseph Rosen. 2023. "Treatment of recurrent carpal tunnel syndrome with fat grafting as an adjunct" Plastic and Aesthetic Research. 10, no.1: 1.

ACS Style

Cabrejo, R.; Podsednik A.; Rosen J. Treatment of recurrent carpal tunnel syndrome with fat grafting as an adjunct. Plast. Aesthet. Res. 2023, 10, 1.

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This article belongs to the Special Issue Tissue Engineering for the Repair of Peripheral Nerve Injury
© The Author(s) 2023. Open Access This article is licensed under a Creative Commons Attribution 4.0 International License (, which permits unrestricted use, sharing, adaptation, distribution and reproduction in any medium or format, for any purpose, even commercially, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons license, and indicate if changes were made.

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