Comparison of Ma-Griffith combined with a minimally invasive small incision to a modified suture technique for the treatment of acute achilles tendon ruptures

Although the Achilles tendon is the strongest tendon in the human body, it is one of the tendons that is most prone to injury and rupture [1]. The annual incidence of Achilles tendon rupture is approximately21.5–24.0 cases per 100,000 persons [2]. The mean age at the time of rupture has been reported to be between 30 and 46 years old, with more men than women acquiring an acute Achilles tendon rupture (male-to-female ratio 2.9–5.7:1) [3, 4] Previous studies have suggested that the most common site of injury is 2–6 cm above the calcaneal tubercle [5, 6]. A recent study found that most acute Achilles tendon ruptures occur between 5 and 8 cm above the distal end of the calcaneal attachment point [7]. Acute Achilles tendon rupture requires early diagnosis and treatment; otherwise, it will lead to lower limb dysfunction that has serious impacts on the patients’ quality of life and work, and creates a heavy economic burden for their families [8].

Currently, the best treatment method for acute Achilles tendon rupture remains controversial 9]. Patients with severe underlying diseases who are unwilling to undergo surgery are usually treated conservatively. However, the rerupture rate after nonoperative treatment is high [10]. Compared with nonoperative treatment, surgery can reduce the incidence of Achilles tendon rerupture, although the incidence of other complications related to surgery, such as nerve injury and incision problems, is significantly higher [11‐13]. Minimally invasive percutaneous repair is less invasive and can reduce the risk of soft tissue complications [14]. However, because the rupture site of the Achilles tendon is not exposed, some percutaneous repair methods can lead to poor involution of the tear site and weak biomechanical resistance [15].

In light of the problems existing with traditional incision repair and minimally invasive repair, we propose a new operative method: the modified Ma-Griffith method combined with minimally invasive small incision (M-G/MISI) surgery. This method is based on percutaneous suture, limited incision under direct vision, and more reliable sutureing of the ruptured tendon edge of the Achilles tendon. We also used a lumbar puncture needle, which greatly reduced the cost of surgery for patients. Currently, in addition to M-G/MISI, the modified suture technique (MST) is also used to treat Achilles tendon rupture in our hospital. The purpose of this study was to compare and analyze the efficacy of the M-G/MISI with that of the MST for the treatment of acute Achilles tendon rupture.

We reviewed and analyzed the medical data of patients who underwent treatment for acute Achilles tendon rupture in the Department of Orthopaedics of the Second Affiliated Hospital of Anhui Medical University of China from January 2012 to January 2020. This study was approved by the local institutional review committee, and the necessary informed consent was obtained.

The best treatment for AATRs remains a topic of debate, with the options of nonoperative, open surgical, minimally invasive, and percutaneous approaches. The main finding of the present study is that M-G/MISI is superior to MST in the treatment of ankle and Achilles function scores after acute Achilles tendon rupture, and the surgical incision in M-G/MISI is smaller.

Numerous randomized studies have been performed comparing operative versus nonoperative treatment, the Achillon technique to open repair, and various percutaneous techniques to open repair, but its treatment is still debated [18]. Numerous surgical procedures have been proposed to repair Achilles tendon rupture. Open surgery ensures tendon repair and improves healing, thus leading to a lower rerupture rate (approximately 2–5%) [19], but complications are common, in up to 34% of cases, including wound infection, skin binding, sural nerve injury, and hypertrophic scarring [20]. Studies have shown that although open repair is the most common surgical technique, surgeons have significant differences in surgical and suture techniques [21]. Percutaneous and minimally invasive techniques combining the benefits of conservatism and openness, such as Ma and Griffith (M&G) or Tenolig, are believed to reduce the risk of complications. Open surgery usually requires a longer incision (approximately 10 cm on average) and too much shedding of the Achilles tendon tissue, which can affect postoperative recovery [22], and large incisions lead to excessive intraoperative blood loss. However, in this study, the average incision length of M-G/MISI was only 3.79 cm (1.81), which was significantly shorter than that with the MST. In a previous randomized controlled study, the clinical and functional scores of patients in the open surgery and percutaneous repair groups were similar, with no significant difference in the incidence of complications between the two groups [23]. However, subsequent studies have found that percutaneous repair of acute Achilles tendon ruptures resulted in fewer complications and higher recovery of activity levels. In our study, there was 1 case of traumatic Achilles tendon rupture in the M-G/MISI group and 1 case each of infection and deep vein thrombosis in the modified suture group. The above results indicate that shorter surgical incisions can effectively reduce intraoperative blood loss and reduce the risk of postoperative infection. Patients undergoing minimally invasive percutaneous surgery generally have a shorter operation time [24], but our results were different and there was no significant difference in the operation time between the two groups. This finding might have been due to the learning curve of surgery, or the number of cases that we included was not sufficient.

Studies have found that compared with minimally invasive surgery, traditional incision repair is more stable but also more prone to infection [25]. In a retrospective analysis of 4,477 patients, Popovic et al. reported that the total incidence of complications was 12.5%; the most common complication was mild incision problems (6.5%), and the rerupture rate was 1.5% [26]. In fact, the problem of incision complications was considered as early as 1977, when Ma-Griffith proposed the Ma-Griffith method [27]. Although this method can reduce the risk of infection and avoid long incisions, the strength of the percutaneous suture has been questioned. Some researchers have studied the method of surgery and found that the rate of rerupture was as high as 8%, and the rate of sural nerve injury was as high as 19% [28]. In comparison with open surgery [29], there were significantly fewer main complications, especially necrosis, in the percutaneous repair group than in the incision repair group, and the total number of complications was smaller.

Adequate repair of Achilles tendon rupture is key to the recovery of ankle joint function. In a recent prospective, randomized clinical trial, the efficacy of open surgery, minimally invasive surgery, and nonoperative treatment for acute Achilles tendon rupture was compared [30]. There were no significant differences in American Orthopedic Foot and Ankle Society ankle-Hindfoot scores among the three treatments at a 24-month follow-up of 69 patients [30]. Different from this RTC, this study used Ma-Griffith combined with a minimally invasive small incision. The results showed that AOFAS and ATRS scores were better in the M-G/MISI group at 6 months after surgery, indicating that the M-G/MISI group had better ankle function recovery.

Sural nerve injury is an important complication of percutaneous minimally invasive surgery. The incidence of sural nerve injury varies with different suture techniques. Lo et al. found that the rate of sural nerve injury in 701 patients was 6.0% [31]. According to different reports, percutaneous repair techniques have different rates of sural nerve injury [32‐34]. When using the percutaneous puncture technique to repair the Achilles tendon, sural nerve injury is inevitable because it cannot be sutured under direct vision. In 2002, Assal et al. conducted a prospective multicenter study using a limited incision and a specially designed device, the Achillon stapler, to ensure that all sutures were placed into the peritendinous tissue, thereby minimizing the risk of implanting suture material into the sural nerve; none of the patients in that study experienced nerve injury [35]. However, this type of operation requires expensive instruments with limited open repair, which placing a significant financial burden on patients. In this study, the reasons for the absence of sural nerve injury in the M-G/MISI group could be the following. First, the surgeons in the M-G/MISI group were familiar with the location of the sural nerve. Second, the sample size of this study was small; therefore, the complication results do not fully reflect the risk of sural nerve injury. No sural nerve injury was found in the MST group, which could be due to the larger surgical incision and less compression or injury of the sural nerve during the operation. Furthermore, the two surgical methods do not use expensive instruments; thus, the cost is not high. Obviously, patients in the M-G/MISI group lost less blood during the operation because of the smaller incision and less damage to the soft tissues during the operation. The possible reasons for the difference in AOFAS and ATRS scores between the two groups six months postoperatively are as follows. First, the MST involves only suturing of the long bundle and short bundle at the ruptured tendon edge, and the contact surface of Achilles tendon recovery in the M-G/MISI group was larger than that with the MST. Second, since the patients were followed up mainly on an outpatient basis, the AOFAS and ATRS scores in the two groups were provided by the two groups of surgeons; thus, subjective factors cannot be excluded.

There are some limitations in this study. Selection bias was not avoided, considering that the surgical treatment to be performed was determined by the orthopedic surgeon. Confounders, such as BMI and underlying medical conditions, were not completely excluded.

In conclusion, this study found that, compared with the MST group, the length of the incision in the M-G/MISI group was smaller, the amount of intraoperative blood loss was less, and the ankle and Achilles tendon function scores for a certain period of time were better than those in the MST group. Therefore, M-G/MISI is less invasive than MST, and the functional score of the M-G/MISI group was better than that of the MST group at the sixth month after operation.