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Injury, Int. J. Care Injured xxx (2018) xxx–xxx
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Utility of early active motion for flexor tendon repair with concomitant injuries: A multivariate analysis Yuki Fujihara* , Hideyuki Ota, Kentaro Watanabe Department of Orthopaedic Surgery, Nagoya Ekisaikai Hospital, 4-66 Shonen-Cho, Nakagawa-Ku, Nagoya, 454-8502, Japan
A R T I C L E I N F O
A B S T R A C T
Article history: Accepted 19 October 2018
Introduction: Flexor tendon injury often occurs with concomitant injuries such as fracture, vascular injury, and extensor tendon injury. These injuries are repaired independently, without a comprehensive strategy. We aimed to identify the effect of concomitant injuries and treatment choice on the outcome of flexor tendon repair. Patients and methods: We evaluated 118 fingers of 102 adult patients with zone 1–3 flexor digitorum profundus (FDP) tendon injuries who underwent primary surgery at our hospital between April 2009 and December 2017. The 2-strand pull-out, 4-strand Tsuge, 6-strand Lim & Tsai, and 8-strand cross-locked cruciate suturing techniques were used. We performed multivariate analyses, with the active range of motion (AROM) of the proximal interphalangeal (PIP) and distal interphalangeal (DIP) joints as dependent variables, and age, existence of concomitant injuries, and their treatment as independent variables. Results: The average AROM of the PIP + DIP joints was 130 at the last follow-up, and ‘excellent’ or ‘good’ function was obtained in 74 (63%) of 118 fingers by using the Strickland criteria. Old age, concomitant diaphyseal fractures, and specific methods of osteosynthesis, such as pinning, flexor digitorum superficialis injury, and immobilisation for 3 weeks, significantly worsened the results. However, wiring for osteosynthesis and early active motion protocol improved postoperative functional outcome. Although the outcome did not differ among the suture techniques, the 4-strand Tsuge procedure was performed for the two surgically confirmed ruptures of repair that occurred in our series. Discussion: We clarified the superiority of early mobilisation protocols with rigid osteosynthesis procedure, other than pinning. To minimise tendon adhesion or joint stiffness, surgeons should repair the tendon and fractured bone appropriately, to ensure early mobilisation without serious complications. © 2018 Elsevier Ltd. All rights reserved.
Key words: Flexor tendon injury Early active motion Complex injury Tendon repair Fracture fixation Prognostic factor
Introduction Flexor tendon injury often occurs with concomitant fractures or extensor tendon injuries, and sometimes requires revascularisation, all of which could aggravate postoperative functional outcome [1–6]. Several authors have reported satisfactory outcomes of flexor tendon repair, excellent or good outcome in 70%– 80% of fingers; however, most of these studies excluded patients with concomitant injuries [7–12]. Rigo and Rokkum [13] performed a retrospective cohort study to identify predictors of outcome after primary flexor tendon repair in 2016. They reported specific prognostic factors, such as smoking, fracture, subzones 1C–2C in Tan’s criteria, certain surgical technique or rehabilitation protocol, and little finger injury [14].
* Corresponding author. E-mail address:
[email protected] (Y. Fujihara).
Although their surgical techniques for FDP tendon repair were 2- to 4-strand methods, which are relatively conventional techniques, the result was unfavourable. Their result elucidated the possible prognostic factors that could improve the outcome. Moreover, they did not report the effect of treatment choice for osteosynthesis despite the fact that the importance of rigid fixation for early mobilisation is widely known [5,15–17]. Thus, the purpose of this study was to identify the factors, including both patient background and treatment factors, which affect the outcome of flexor tendon repair. Patients and methods This retrospective observational study was approved by our institutional review board, and informed consent was waived due to the retrospective design. This study was conducted at a single general hospital. We performed a retrospective review of the institution’s electronic medical records from April 2009 to
https://doi.org/10.1016/j.injury.2018.10.022 0020-1383/© 2018 Elsevier Ltd. All rights reserved.
Please cite this article in press as: Y. Fujihara, et al., Utility of early active motion for flexor tendon repair with concomitant injuries: A multivariate analysis, Injury (2018), https://doi.org/10.1016/j.injury.2018.10.022
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December 2017 to identify patients who underwent primary repair of flexor digitorum profundus (FDP) tendons in zones 1–3 [18]. The exclusion criteria were as follows: age <18 years, incomplete FDP tear, primary arthrodesis at the proximal interphalangeal (PIP) or distal interphalangeal (DIP) joint, only insufficient data available, and a follow-up period <3 months. Each surgeon performed simple tendon repair and chose postoperative rehabilitation protocol depending on their preference and the condition of the tendon. We included 118 fingers of 102 patients (76 men and 26 women) in this study. The detailed flow chart of patient inclusion is shown in Fig.1. The mean follow-up period in our study was 7 6 months (mean SD), and the treatment outcome was examined at the final follow-up. Following the Strickland criteria, we defined PIP and DIP joint active range of motion (DIP + PIP-joint AROM) as a primary outcome [19]. We extracted data such as age, duration from injury to primary repair of flexor tendon, involved finger, mechanism of injury, location of flexor rupture, existence of concomitant flexor digitorum superficialis (FDS) injury, diaphyseal or intraarticular fractures, extensor tendon injury, skin defect, vascular injury in the injured finger, and fracture or tendon injury in the adjacent finger as patient background factors. Following a previous study, we categorised the mechanism of injury as either sharp or saw/tear injury [20]. We obtained data of employed rehabilitation protocols, utilised suture techniques, conducted osteosynthesis techniques, and level of experience of surgeons as treatment factors [21]. We selected 2-strand pull-out technique, 4-strand Tsuge technique, 6-strand Lim & Tsai technique, and 8-strand cross-locked cruciate technique depending on surgeon’s preference [22–25]. We selected the types of rehabilitation protocol, such as 3-week immobilisation protocol, active extension and passive flexion using rubber band in the splint (modified Kleinert protocol), and early active flexion protocol, for each patient based on their individual circumstances, character, compliance, and preference [26–28]. All of these factors were included as possible prognostic factors. Statistical analysis Because DIP + PIP-joint AROM is a continuous variable, we used a linear regression model to identify prognostic factors for the loss of DIP + PIP-joint AROM. We built a multivariate model using backward stepwise regression, stopping when all remaining covariates were significant at an α level of 0.05. We reported partial regression coefficient for the primary outcome, 95% confidence intervals (95% CIs), and P values for the multivariate result. All statistical analyses were performed with EZR version
Fig. 1. Flow chart of patient inclusion. DIP: distal interphalangeal, PIP: proximal interphalangeal.
1.37 (Saitama Medical Center, Jichi Medical University, Saitama, Japan), which is a graphical user interface for R (The R Foundation for Statistical Computing, Vienna, Austria) [29]. EZR is a modified version of R commander designed to add statistical functions frequently used in biostatistics. Results The average AROM of the DIP and PIP joints at the final followup was 130 in this series, and 74 fingers (63%) achieved good or excellent function according to the original Strickland criteria [19]. Basic information and sample size of each category are shown in Table 1. In univariate linear regression analysis, higher patient age (P = 0.0009) and concomitant diaphyseal fracture (P = 0.021) were the significant factors that aggravated the final result of DIP + PIP joint AROM. Multivariate linear regression analysis showed that patients with higher age, phalangeal or intraarticular fracture in the injured finger, particularly fixed with pinning technique, concomitant FDS injury, and those who underwent specific postoperative rehabilitation protocol, the 3-week immobilisation protocol, had worse DIP + PIP joint AROM (Table 2). With regard to postoperative complication, we encountered 2 cases of surgically confirmed ruptures of the repair in this series, both of which underwent 4-strand Tsuge procedure with early active mobilisation protocol. Fourteen fingers underwent tenolysis of the repaired flexor tendon, and only 6 fingers in this group achieved excellent or good result. Nine in 16 fingers were repaired with 4-strand Tsuge procedure. Discussion In the current study, we aimed to identify the prognostic factors that determine the outcome of flexor tendon repair, and found several factors that could affect the outcome. In addition to the unmodifiable factors, such as old age, FDS tendon injury, and concomitant diaphyseal fractures, certain treatment options, such as pinning and immobilisation for 3 weeks, significantly worsened the results. The choice of suture technique was not a significant prognostic factor in our series; however, the two surgically confirmed ruptures of the repair occurred after 4-strand Tsuge procedure. The efficacy of early active mobilisation after flexor tendon repair is widely known to minimise adhesion formation and prevent joint stiffness [30,31]. Gelberman et al. [32] reported the efficacy of active use after tendon repair, which strengthens the tensile strength compared with continuous immobilisation. The result of our study verified the superiority of early active mobilisation to immobilisation protocol, even on the fingers with complex injuries. The effect of fracture or other concomitant injuries on the repair of flexor tendon remains unknown. Most of the basic studies focusing on the flexor tendon repair used clean cut tendon without any fracture model [33–36]. To date, studies identifying whether concomitant injuries increase the resistance of tendon gliding and delay the healing of sutured site have not made much progress. The finding verified in the present study could encourage further investigation of these studies. The choice of suture technique is another key point in flexor tendon repair. Recently, hand surgeons usually have been using at least 4-strand suture in clinical practice, and the tensile strength increases with greater number of suture strand crossing the repair site [33,36–39]. Boyer et al. identified far greater tensile strength of 8-strand repair than that of 4-strand repair. In this study, no difference was found in the final result among three suture techniques, namely, 4-strand Tsuge technique, 6-strand Lim & Tsai technique, and 8-strand cross-locked cruciate technique. However, we encountered 2 cases of ruptures of repair in this series, both of
Please cite this article in press as: Y. Fujihara, et al., Utility of early active motion for flexor tendon repair with concomitant injuries: A multivariate analysis, Injury (2018), https://doi.org/10.1016/j.injury.2018.10.022
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Y. Fujihara et al. / Injury, Int. J. Care Injured xxx (2018) xxx–xxx Table 1 Prognostic factors and DIP + PIP joint AROM. Sample size
Table 2 Multivariate linear regression analysis of Final DIP + PIP AROM. Mean AROM
Finger Index Long Ring Little
SE
P value
1.1
0.2
≦0.01
67.8 31.2
– 18.3 19.27
– ≦0.01 0.11
– 19.2 24.9 25.6 31.0
– 0.70 0.88 0.19 ≦0.01
– 7.4 12.8
– 0.01 ≦0.05
– 8.6 8.5
– ≦0.01 0.02
Patient age
29 89
34 29 23 32
37.0
13.9
134.1 128.7
57. 5 47.1
128.6 136.6 135.1 122.0
50.8 47.3 47.3 53.1
2.7
4.8
Duration from injury to repair
Mechanism of injury Sharp Saw/Tear
59 59
147.5 112.5
42.9 50.1
Injured zone Zone 1 Zone 2 Zone 3
37 76 5
138.8 126.1 125.0
31.1 54.9 77.1
Fracture None Diaphysis Intraarticular
87 20 11
145.0 80.5 102.0
42.3 40.9 50.6
FDS repair None Sutured/Repair Resection
51 54 13
141.9 124.8 105.2
38.3 54.8 57.2
Extensor tendon Normal Injured
99 19
137.9 92.1
47.0 40.1
Skin Normal Defect
110 8
132.7 92.8
49.8 30.0
Vascularisation Normal Revascularised
92 26
138.7 99.4
45.6 52.2
Adjacent finger Normal Injured
82 36
136.6 115.0
47.3 52.2
Rehabilitation protocol 3 weeks immobilisation Modified Kleinert Early active flexion
56 30 32
120.4 155.6 122.8
47.4 39.9 54.6
Suture technique Pull out Tsuge Lim & Tsai 8-strand cross-locked cruciate
10 48 39 21
137.7 128.3 143.1 106.0
34.0 49.0 46.4 56.8
Osteosynthesis None Pinning Plate Wiring Joint fusion
92 16 4 4 2
141.0 79.5 72.5 118.0 170.0
45.6 32.2 50.6 38.2 56.6
Level of surgeon Level 1 Level 2 Level 3 Level 4
50 7 44 17
117.3 92.1 149.6 132.4
52.1 67.7 36.1 48.2
FDS: flexor digitorum superficialis. AROM: active range of motion.
Estimate
SD
Patient age Sex Female Male
3
Fracture None Diaphysis Intraarticular Osteosynthesis None Pinning Plate Wiring Joint fusion FDS repair None Sutured/Repair Resection Rehabilitation protocol 3 weeks immobilisation Modified Kleinert Early active flexion
–
– 7.3 3.7 33.5 84.0
– 21.1 25.5
– 30.6 20.3
FDS: flexor digitorum superficialis.
which underwent 4-strand Tsuge technique. To minimise the possibility of critical complication, we recommend the use of at least 6-strand suture technique, particularly for the repair of flexor tendon with complex injuries. With regard to the treatment choice of osteosynthesis, our data showed the superiority of wiring technique to K-wire pinning or plating. As previously mentioned, early active motion with 6 or greater number of strand suture is necessary to obtain preferable result. To achieve this goal, rigid fixation with minimum friction between employed implant and gliding tendons is required. This study had several limitations. First, we could not conclude causation because of its retrospective nature. Further prospective study is necessary to clarify our findings. Second, our study had a relatively small sample size. Although we performed backward stepwise regression to reduce the number of variables, this could reduce the quality of our study. Finally, we did not analyse the efficacy of peripheral suture, which can increase the strength of repaired site. Despite these limitations, we could suggest the importance of rigid osteosynthesis in the treatment of concomitant fractures to improve the outcome of flexor tendon repair based on the clinical data. The results of our study might promote basic research, biomechanical studies, or clinical studies with larger samples to elucidate the causation and to establish the systematic treatment strategy for such complicated injuries. Conclusion Our study clarified the importance of early active motion protocol for flexor tendon laceration with complex injuries to achieve better postoperative functional outcome. For this purpose, rigid osteosynthesis with strong suture technique enough to tolerate early active motion is necessary. Although the condition of each case could largely differ, a certain strategy should be developed based on evidence to improve the functional outcome of these not-so-rare complex injuries. Role of the funding source The authors have no funding to report.
Please cite this article in press as: Y. Fujihara, et al., Utility of early active motion for flexor tendon repair with concomitant injuries: A multivariate analysis, Injury (2018), https://doi.org/10.1016/j.injury.2018.10.022
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Conflicts of interest None. References [1] James J.I.. Fractures of the proximal and middle phalanges of the fingers. Acta Orthop Scand 1962;32:401–12. [2] Huffaker WH, Wray Jr RC, Weeks PM. Factors influencing final range of motion in the fingers after fractures of the hand. Plast Reconstr Surg 1979;63:82–7. [3] Chow SP, Pun WK, So YC, Luk KDK, Chid KY, Ng KH, et al. A prospective study of 245 open digital fractures of the hand. J Hand Surg Br 1991;16:137–40. [4] Duncan RW, Freeland AE, Jabaley ME, Meydrech EF. Open hand fractures: an analysis of the recovery of active motion and of complications. J Hand Surg Am 1993;18:387–94. [5] Ip WY, Ng KH, Chow SP. A prospective study of 924 digital fractures of the hand. Injury 1996;27:279–85. [6] Mayer L. The physiological method of tendon transplants reviewed after forty years. Instr Course Lect 1956;13:116–20. [7] Baktir A, Turk CY, Kabak S, Sahin V, Kardas Y. Flexor tendon repair in zone 2 followed by early active mobilization. J Hand Surg Br 1996;21:624–8. [8] Cullen KW, Tolhurst P, Lang D, Page RE. Flexor tendon repair in zone 2 followed by controlled active mobilisation. J Hand Surg Br 1989;14:392–5. [9] Elliot D, Moiemen NS, Flemming AF, Harris SB, Foster AJ. The rupture rate of acute flexor tendon repairs mobilized by the controlled active motion regimen. J Hand Surg Br 1994;19:607–12. [10] Moriya K, Yoshizu T, Maki Y, Tsubokawa N, Narisawa H, Endo N. Clinical outcomes of early active mobilization following flexor tendon repair using the six-strand technique: short- and long-term evaluations. J Hand Surg Eur Vol 2015;40:250–8. [11] Tang JB. Clinical outcomes associated with flexor tendon repair. Hand Clin 2005;21:199–210. [12] Tang JB. Outcomes and evaluation of flexor tendon repair. Hand Clin 2013;29:251–9. [13] Rigo IZ, Rokkum M. Predictors of outcome after primary flexor tendon repair in zone 1, 2 and 3. J Hand Surg Eur Vol 2016;41:793–801. [14] Tang JB. Flexor tendon repair in zone 2C. J Hand Surg Br 1994;19:72–5. [15] Day CS. Fractures of the metacarpals and phalanges. In: Wolfe SW, Hotchkiss RN, Pederson WC, Kozin SH, Cohen MS, editors. Green’s operative hand surgery. 7th ed. Philadelphia, PA: Elsevier; 2017. p. 231–77. [16] Chow SP, Pun WK, So YC, Luk KD, Chiu KY, Ng KH, et al. A prospective study of 245 open digital fractures of the hand. J Hand Surg Br 1991;16:137–40. [17] Hastings 2nd H. Unstable metacarpal and phalangeal fracture treatment with screws and plates. Clin Orthop Relat Res 1987;37–52. [18] Verdan CE. Half a century of flexor-tendon surgery. Current status and changing philosophies. J Bone Joint Surg Am 1972;54:472–91. [19] Strickland JW, Glogovac SV. Digital function following flexor tendon repair in Zone II: a comparison of immobilization and controlled passive motion techniques. J Hand Surg Am 1980;5:537–43. [20] Starnes T, Saunders RJ, Means Jr. KR. Clinical outcomes of zone II flexor tendon repair depending on mechanism of injury. J Hand Surg Am 2012;37:2532–40.
[21] Tang JB. Re: levels of experience of surgeons in clinical studies. J Hand Surg Eur Vol 2009;34:137–8. [22] Lee SK, Fajardo M, Kardashian G, Klein J, Tsai P, Christoforou D. Repair of flexor digitorum profundus to distal phalanx: a biomechanical evaluation of four techniques. J Hand Surg Am 2011;36:1604–9. [23] Chauhan A, Palmer BA, Merrell GA. Flexor tendon repairs: techniques, eponyms, and evidence. J Hand Surg Am 2014;39:1846–53. [24] Gill RS, Lim BH, Shatford RA, Toth E, Voor MJ, Tsai TM. A comparative analysis of the six-strand double-loop flexor tendon repair and three other techniques: a human cadaveric study. J Hand Surg Am 1999;24:1315–22. [25] Watanabe K, Ota H, Sasaki H. Eight-strand cross-locked cruciate flexor tendon repair using double-stranded suture: a description of the surgical technique. Plast Reconstr Surg Glob Open 2016;4:e1048. [26] Kleinert HE, Kutz JE, Atasoy E, Stormo A. Primary repair of flexor tendons. Orthop Clin North Am 1973;4:865–76. [27] Lister GD, Kleinert HE, Kutz JE, Atasoy E. Primary flexor tendon repair followed by immediate controlled mobilization. J Hand Surg Am 1977;2:441–51. [28] Chow JA, Thomes LJ, Dovelle S, Milnor WH, Seyfer AE, Smith AC. A combined regimen of controlled motion following flexor tendon repair in “no man’s land”. Plast Reconstr Surg 1987;79:447–55. [29] Kanda Y. Investigation of the freely available easy-to-use software ‘EZR’ for medical statistics. Bone Marrow Transplant 2013;48:452–8. [30] Tang JB. Indications, methods, postoperative motion and outcome evaluation of primary flexor tendon repairs in Zone 2. J Hand Surg Eur Vol 2007;32:118– 29. [31] Chesney A, Chauhan A, Kattan A, Farrokhyar F, Thoma A. Systematic review of flexor tendon rehabilitation protocols in zone II of the hand. Plast Reconstr Surg 2011;127:1583–92. [32] Gelberman RH, Manske PR, Akeson WH, Woo SL, Lundborg G, Amiel D. Flexor tendon repair. J Orthop Res 1986;4:119–28. [33] Winters SC, Gelberman RH, Woo SL, Chan SS, Grewal R, Seiler [54_TD$DIFF] [51_TD$DIFF]3rd JG. The effects of multiple-strand suture methods on the strength and excursion of repaired intrasynovial flexor tendons: a biomechanical study in dogs. J Hand Surg Am 1998;23:97–104. [34] Lin TW, Cardenas L, Soslowsky LJ. Biomechanics of tendon injury and repair. J Biomech 2004;37:865–77. [35] Gelberman RH, Boyer MI, Brodt MD, Winters SC, Silva MJ. The effect of gap formation at the repair site on the strength and excursion of intrasynovial flexor tendons. An experimental study on the early stages of tendon-healing in dogs. J Bone Joint Surg Am 1999;81:975–82. [36] Thurman RT, Trumble TE, Hanel DP, Tencer AF, Kiser PK. Two-, four-, and sixstrand zone II flexor tendon repairs: an in situ biomechanical comparison using a cadaver model. J Hand Surg Am 1998;23:261–5. [37] Dinopoulos HT, Boyer MI, Burns ME, Gelberman RH, Silva MJ. The resistance of a four- and eight-strand suture technique to gap formation during tensile testing: an experimental study of repaired canine flexor tendons after 10 days of in vivo healing. J Hand Surg Am 2000;25:489–98. [38] Strickland JW. Flexor tendon injuries: I. Foundations of treatment. J Am Acad Orthop Surg 1995;3:44–54. [39] Boyer MI. Flexor tendon biology. Hand Clin 2005;21:159–66.
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