Comparison of Maylard and Cherney incisions' outcomes in hysterectomy surgery for benign indications: a double-blind randomized controlled trial

Abstract

Objectives

Choosing the incision for surgery depends on a variety of factors, including the surgeon's preference, patient preference, surgical indications, the patient's systemic issues, previous surgical scars, and other considerations. This trial aimed to evaluate and compare the surgical outcomes of two techniques—Maylard and Cherney incisions—in benign hysterectomy procedures for women.

Materials and methods

A randomized controlled trial was conducted in Al-Zahra Women’s Tertiary Referral University Hospital. A total of 60 patients undergoing benign hysterectomy were randomly allocated to two groups, with one group undergoing surgery with a Maylard incision and the other with a Cherney incision. Surgeries in both groups were performed by a gynecologist oncologist who was a member of the university faculty, accompanied by an Obstetrics and Gynecology Resident.

Results

There were no significant differences in hemoglobin levels or clinical or obstetric characteristics before surgery between the two study groups (p > 0.05). The mean time from skin incision to entering the abdominal cavity was 14.23 min for Maylard and 13.6 min for Cherney (p = 0.091). The average blood loss was 506.6 mL in the Maylard group and 429.3 mL in the Cherney group, which was statistically significant (p = 0.031). Postoperative hemoglobin levels were 11.68 g/dL in the Maylard group and 12.07 g/dL in the Cherney group (p = 0.133). Pain scores were higher in the Cherney group than in the Maylard group (p = 0.041). There were no surgical complications after 1 and 3 months in the study groups.

Conclusions

No complications were observed in any of the patients following the surgery. The Mylard incision showed a higher level of bleeding in comparison with the Cherney incision, which was linked to more noticeable pain. Nevertheless, both incisions are deemed as effective options for gynecological surgeries, offering superb visibility to the pelvis.

Introduction

Gynecological surgeries are some of the most frequently performed surgical procedures. The selection of the incision type for surgery is influenced by several factors, such as the surgeon's expertise and preference, the patient's preference, the surgical indication, underlying pathology, suspicion of malignancy, previous surgical scars, and comorbidities [1, 2]. Transverse incisions have been utilized for around 200 years and provide several advantages over midline incisions. These benefits include improved cosmetic results, decreased postoperative pain, lowered risk of wound dehiscence, reduced incidence of incisional hernias and adhesions, as well as fewer pulmonary complications [3, 4]. Moreover, non-midline incisions are advised as a means to lower the probability of developing incisional hernias [5, 6]. The Pfannenstiel incision is a widely utilized technique in gynecological and obstetric surgeries. However, a notable limitation of this approach is its restricted surgical exposure [7]. Sufficient visibility of the operative field is crucial for the overall success of surgical procedures. In 1907, Ernest Maylard introduced a pioneering incision technique [8]. The Maylard technique involves a transverse incision that cuts through all abdominal layers, from the skin to the peritoneum. The inferior epigastric vessels are ligated and cut at the lateral edges of the rectus muscles, with the skin incision site typically positioned 3–8 cm above the symphysis pubis [9, 10].

The Maylard incision, being a transverse incision, not only produces aesthetically pleasing scar outcomes but also ensures exceptional visibility of the pelvic floor and abdomen [11]. While the Maylard incision is known for causing less postoperative pain and necessitating fewer analgesics in comparison with the Pfannenstiel incision [12], certain research studies have indicated that it may result in lengthier surgical procedures, heightened intraoperative blood loss, and hematomas stemming from incorrect ligature of the epigastric vessels. Another downside of the Maylard incision is that the healing of the muscles, along with fibrosis, may result in weakening of the rectus muscle at the incision site [13,14,15].

The Maylard incision's limited acceptance among surgeons may stem from their hesitance to dissect the rectus muscles, despite the fact that incisional hernia results with this technique tend to be more positive in comparison with vertical incisions [12, 13]. In 1941, the Cherney incision was developed to address surgeons' concerns about making a transverse cut in the rectus muscles. This incision aimed to avoid muscle weakening while incorporating the advantages of both the Maylard and Pfannenstiel incisions [16]. The Cherney incision is essentially a variation of the Maylard incision, showing similarities to the Pfannenstiel incision but providing improved surgical exposure [17]. After surgery, it helps decrease abdominal bloating and alleviate discomfort when taking deep breaths, coughing, sneezing, and moving. Pulmonary issues related to this type of incision are uncommon, as the wound remains robust due to the absence of muscle denervation. When performing the Cherney technique, a surgical incision is made in the skin one to two centimeters below and toward the midline of the anterior superior iliac spine (ASIS). The rectus muscles are subsequently divided about half a centimeter away from their insertion point on the pubis at the ligamentous junction [13]. One benefit of utilizing this incision is the enhanced visibility of the surgical area, especially advantageous in obese patients [16].

Among the transverse incisions in the field of women, the Pfannenstiel incision is widely used; however, it provides limited exposure to the abdomen and pelvis. Other transverse incisions, such as the Maylard and Cherney incisions, despite being recommended in guidelines and advanced surgeries like Accreta, are not frequently utilized, and there are few articles addressing these two incisions [18]. Therefore, this study was conducted to evaluate the effectiveness and safety of these two incisions in gynecological surgeries. One notable difference in this field is that when a Pfannenstiel incision is made but does not provide sufficient exposure, it can be converted to a Cherney incision rather than a Maylard incision. Limited evidence exists comparing the benefits of the Cherney incision to the Maylard incision in gynecological surgeries, specifically in hysterectomies [19,20,21]. Some evidence suggests that both the Maylard and Cherney incisions are utilized for hysterectomies involving placenta accreta. However, there is a limited comparison of the advantages and outcomes of these two techniques, making it challenging for surgeons to determine the most suitable method based on the specific indication [22]. In addition, past research has often contrasted the Cherney technique with Pfannenstiel or midline [14, 23, 24]. No clinical trial has yet been conducted to compare the Maylard and Cherney incisions prior to this current study. Thus, this randomized controlled trial (RCT) aims to compare the surgical outcomes of the Maylard and Cherney incision techniques in benign hysterectomy procedures for women.

Methods

Study design and setting

This parallel randomized controlled trial (RCT) compared patients undergoing hysterectomy for benign reasons in two groups. One group underwent surgery with the Maylard incision, while the other group underwent surgery with the Cherney incision. The research sample comprised women who had a hysterectomy for benign conditions and were directed to Al-Zahra Women’s Hospital within a 1-year period beginning in January 2023. Al-Zahra Women’s Teaching Hospital serves as a specialized referral facility for women's health in the northwestern region of Iran.

Eligibility

The study's inclusion criteria required participants to have undergone a hysterectomy for benign conditions, be aged between 35 and 65 years, and give informed consent. The exclusion criteria comprised individuals with an abdominal wall hernia and intra-abdominal adhesion, diabetes, systemic diseases necessitating corticosteroid treatment within the previous 6 months, documented thrombophilia, ongoing anticoagulant therapy, recent chemo radiation or malignancies within the last 6 months, a body mass index exceeding 30, tobacco use, and a history of more than two prior abdominal surgeries.

Sample size

Based on our pilot study and previous surgical experience, the average blood loss in surgeries using the Maylard technique was reported to be 510 ± 140 ml, while with the Cherney technique, it was 420 ± 110 ml. To maintain a statistical power of 80% and control for a Type I error of α = 0.05, we determined that a minimum of 30 patients per group was necessary. Hence, a total sample size of 60 patients was deemed appropriate for this study.

Participants and randomization

Patients with indications for benign hysterectomy were randomly assigned to two groups: one group for surgery using the Maylard incision and the other for surgery using the Cherney incision. Randomization was conducted using a balanced block randomization method, with each block consisting of 4 participants and a total of 15 blocks (see Fig. 1). The block order and allocation sequence were determined by a methodologist using random concealment with STATA software version 14. All patients, data collectors, and the statistical analyst were kept blinded to the study groups and the type of incision utilized.

Fig. 1

Consort flow diagram

Surgical method

The surgical method and procedures were the same for both groups in terms of incision methods, and were carried out using a consistent technique. All surgeries were conducted by a gynecologist oncologist who is a member of the university faculty, with an Obstetrics and Gynecology Resident in attendance. The type of incision used was only known to the operating surgeon, as implementing blinding was not feasible. Here’s a revised version of your text. All patients underwent standard general anesthesia. After making the incision (either Maylard or Cherney), a standardized approach was employed for the hysterectomy. Delayed absorbable sutures of uniform size and needle type were utilized across all patients.

Each patient received 2 g of intravenous Cefazolin as prophylactic antibiotics. If needed, diclofenac sodium suppositories were used for pain management, and injectable pethidine was administered for severe pain. All patients were monitored in a postoperative care unit. Transition from NPO (nothing by mouth) to oral intake occurred once bowel sounds were detected, and the Foley catheter was removed within 12–24 h post-surgery. Patients were encouraged to mobilize as soon as they regained their physical capabilities.

Measurements

Patient information was gathered using a standardized checklist for both study cohorts. This checklist comprehensively covered demographic and baseline characteristics, along with detailed obstetric data. Obstetric information encompassed gravidity, parity, total number of live births, incidences of miscarriages, and past history of both vaginal and cesarean deliveries.

Surgical parameters analyzed included the duration from incision to entry into the abdominal cavity and the overall surgical duration, with both measurements recorded in minutes. Blood loss was evaluated through two distinct methodologies:

• 1. Laboratory method: Comparison of hemoglobin levels pre- and post-surgery

• 2. Observational method: Estimating blood loss by assessing the volume of blood collected in the suction device, the quantity of blood-soaked gauze and lap sponges gathered during the procedure, and the amount of blood lost at the surgical site and on drapes.

Pain intensity and severity were assessed in the initial 3 days post-operation through the application of the Visual Analog Scale (VAS). The VAS measurements were conducted bi-daily at 8:00 a.m. and 4:00 p.m. Each VAS score ranged from 0 to 10, with 0 signifying no pain and 10 representing the most intense pain. Pain scores were meticulously documented and gathered in accordance with the study protocol. The frequency of analgesic use after surgery was also recorded. Abdominal distension was evaluated post-surgery. Criteria such as the absence of bowel sounds within 12 h after the operation, tympany upon palpation, and abdominal swelling were used to assess abdominal distension. Patients were monitored monthly for up to 3 months following the surgery. During these subsequent visits, wound complications, such as hematoma, infection, and wound dehiscence, as well as incisional hernias, and any hospital readmissions related to surgical complications, were carefully examined and documented.

Outcomes

The primary outcomes of the study encompassed the following: the duration of the surgical incision until entry into the abdominal cavity, the volume of blood loss, hemoglobin levels before and after surgery, and the total duration of the surgery. Secondary outcomes involved pain intensity, the frequency of analgesic medication administration, post-procedure abdominal distension, as well as any surgical complications observed at the 1- and 3-month follow-ups.

Data analysis

Data analysis was conducted using SPSS (version 22.0, Chicago, IL, USA). The normality of the data was assessed through Q–Q plots and the Shapiro–Wilk test. To compare quantitative variables between the two groups, we employed the independent T test for parametrically distributed data and the Mann–Whitney U test for non-parametrically distributed data. The Chi-square (χ²) test was utilized for comparing binary or categorical variables between the groups. Fisher's exact test was utilized if the expected frequency in any cell of a 2 × 2 table was below 5 [25]. A significance level of less than 5% was considered for all statistical tests.

Results

A total of 60 patients eligible for benign hysterectomy were analyzed, with 30 undergoing the Maylard technique and 30 undergoing the Cherney technique in the Maylard group. Table 1 displays the demographic, clinical, and obstetric features of the study participants. The average age of patients in the Maylard and Cherney groups was 46 and 48 years, respectively, showing no significant statistical difference (P = 0.497). The mean body mass index (BMI) was 26.85, while in the Cherney group it was 28.4. However, this difference was not found to be statistically significant (P = 0.179). Gravidity and parity also showed no significant variations between the two groups, with similar values observed in Maylard and Cherney groups for gravidity (2.43 vs. 2.22) and parity (2.43 vs. 2.39) (P > 0.05). There were no notable variations in the number and percentage of given birth (childbirth), cesarean section, and the history of abdominal surgeries including total abdominal hysterectomy, myomectomy, salpingectomy, and cystectomy (P > 0.05). Similarly, the hemoglobin levels before surgery did not differ significantly between the two groups (P = 0.348). Furthermore, there was no history of uterine adhesion among all the patients in the study groups.

Table 1 Clinical and obstetric characteristics of the participants at the baseline

In Fig. 2, the average pain scores based on the VAS for both incision methods are illustrated for the first, second, and third days, measured during both morning and afternoon. The pain scores for each incision method are displayed individually for each day and time. It is noted that the pain score was notably higher in the Cherney incision group compared to the Maylard group. Furthermore, a trend analysis revealed that this disparity was statistically significant (P = 0.042).

Fig. 2

Comparison of pain score (VAS*) between Maylard and Cherney incision techniques (P = 0.042) **. * VAS: Visual Analogue Scale. ** Cochran–Armitage test for trend

Table 2 presents a comparison of blood loss and study outcomes across the groups. The mean duration from skin incision to entry into the abdominal cavity was 14.23 min for the Maylard technique and 13.6 min for the Cherney technique, showing no significant difference (P = 0.091). In addition, there was no notable contrast in the total surgical time between the Maylard (125.3 min) and Cherney (136.2 min) techniques (P = 0.275). However, the average blood loss following the Maylard incision was 506.6 ml, as opposed to 429.3 ml for the Cherney incision, demonstrating a statistically significant variance (P = 0.031). Hemoglobin levels post-operation were 11.68 g per deciliter in the Maylard group and 12.07 g per deciliter in the Cherney group, with this disparity not being statistically significant (P = 0.133).

Table 2 Comparison of bleeding rate and outcomes by the study groups

The administration of analgesics was significantly different between the Maylard group (2.83 times) and the Cherney group (4.06 times) (P = 0.001). On the first day, 4 out of 30 patients in the Maylard group did not report pain in the morning session compared to 2 in the Cherney group. During the afternoon session, 5 patients in the Maylard group were pain-free, while none were in the Cherney group, which was statistically significant (P = 0.019). The Maylard group also had more pain-free patients on the second day compared to the Cherney group, especially in the afternoon session (P = 0.007). However, on the third day, although there were more pain-free patients in the Maylard group in both morning and afternoon sessions, the difference was not statistically significant. There were no observed adverse effects of surgery or re-hospitalization in either group up to 1 and 3 month post-surgery (Table 2).

Discussion

This trial compared two incision techniques in gynecological surgery for benign hysterectomy, marking the first of its kind to examine the outcomes of these procedures. The research sheds light on decision-making within the realm of hysterectomy surgery, with findings indicating notably higher blood loss with the Maylard technique compared to the Cherney technique. The average blood loss observed during procedures utilizing the Maylard technique was significantly greater. Considering that the Maylard incision is made at the level of the Anterior, Superior, Iliac, Spine (ASIS), the rectus abdominis muscle is cut. In contrast, the Cherney incision involves cutting the ligament without affecting the blood vessels of the rectus muscle. Consequently, there is more bleeding associated with the Mylard incision [18]. Blood loss measurement methods included visual assessments through suction device usage and accountable blood-soaked gauze, alongside clinical evaluations of pre- and post-surgical hemoglobin levels. While the postoperative hemoglobin levels in the Maylard group appeared lower than those in the Cherney group, the statistical significance of this discrepancy remains uncertain. Visual indications suggest a higher volume of blood loss. These results resonate with Scribner et al.'s study, revealing that the Maylard technique, in addition to increased intraoperative blood loss, led to extended surgical durations [26]. To ensure accurate outcomes and reduce potential bias, we have implemented several measures. These include adopting balanced block randomization for participant allocation, assessing obstetric and clinical variables before surgery in both groups and ensuring their balance prior to study commencement, having surgical procedures carried out by a single surgeon, and maintaining blinding protocols for data collectors and analysts.

Prior to 1890, gynecological and obstetric surgeries involved vertical skin incisions. However, pioneering work by Kushner and Rapin in 1890 introduced the use of transverse skin incisions for such procedures. In 1987, Pfannenstiel emphasized the importance of standard abdominal incisions possessing key characteristics, such as safety, ease of entry into the peritoneal space, and adequate exposure. In addition, it was noted that closing the incision should result in minimal damage to surrounding organs and be free of complications [27, 28].

In the current study, postoperative pain levels were monitored every 12 h for a duration of 3 days using the VAS scale. Pain intensity exhibited a gradual decrease over the course of the study for both the Cherney and Maylard groups. Notably, the Cherney group consistently reported elevated levels of pain compared to the Maylard group, leading to a higher frequency of analgesic administration in the former. Our results align with previous research by Lee-Parritz et al., indicating that the Maylard incision resulted in lesser postoperative pain when compared to the Pfannenstiel incision [29]. A retrospective cohort study conducted by N. Atobiloye et al. further corroborated these findings, highlighting that while the Cherney incision was associated with increased complications, pain levels were comparatively lower in both Cherney and Maylard groups as opposed to Pfannenstiel [30]. Moreover, Lee et al. conducted a comparative study between modified Cherney incisions and vertical midline incisions in cervical cancer patients. The outcomes revealed that patients undergoing surgery with the Cherney incision exhibited quicker initiation of a soft diet and shorter hospital stays. However, no significant variations were observed in terms of pain intensity or hemoglobin levels [20]. In relation to the increased pain associated with the Cherney incision compared to the Maylard incision, this may be attributed to the fact that in the Cherney technique, the muscles are reattached with sutures to the lower rectus flap, whereas in the Maylard incision, the muscles are not sewn separately. Consequently, post-operative pain may be more pronounced in Cherney incisions. In addition, other factors, including the type and size of the incision, the timing of the surgery (which was greater in the Cherney), and the skill and experience of the surgeon (we utilized only one surgeon in this study to eliminate any confounders) could account for the heightened pain in the Cherney incision [21, 31, 32].

In the current study, no surgical complications or re-hospitalizations were reported in any of the patient groups after 1 and 3 months of follow-up, which the authors consider a significant finding indicating successful surgery outcomes. Analysis of the time taken from skin incision to entry into the abdominal cavity and the overall duration of the surgery revealed no substantial variances between the two incision methods, with no complications observed in either technique. Previous research (references [33, 34] has suggested that both Maylard and Cherney incisions, though enhancing cosmetic results, are associated with fewer complications. In a study by Orr et al., comparing 113 patients with midline incisions to 78 patients with transverse incisions, it was noted that surgical duration, intraoperative blood loss, and transfusion requirements were notably lower in the transverse incision group. The average hospital stay was 5.6 days for the transverse incision group and 7.5 days for the midline incision group (reference [35]. Similarly, De Lia et al. found that the Cherney incision resulted in fewer postoperative complications in surgeries involving large fibroids compared to the midline incision. Contrary to previous findings, no complications were observed in the current study [21]. Recent studies have suggested the utilization of Maylard and Cherney incision techniques for cancer surgeries, advanced procedures necessitating optimal exposure during the operation [8, 20, 36].

Limitations and strengths

The findings of the current research encompassed factors, such as bleeding, hemoglobin levels, pain, and surgical duration, all of which are susceptible to the impact of various variables and confounders. To tackle these challenges:

Consistent surgical approach: a single gynecologic oncologist was utilized for all surgical procedures. Random assignment: participants were randomly assigned to either group using block randomization. Baseline and obstetric variables: as none of the baseline and obstetric variables showed statistical significance between the groups, there was no need for regression analysis to control for confounding variables. Blinding and concealment: our implementation of blinding and concealment methods was to safeguard against information bias and guarantee that data collection and analysis were carried out impartially.

Another concern was that the study groups did not provide data on the size of the uterus. However, measuring all basic and obstetric variables and employing random allocation ensures a balanced distribution of these variables across the study groups. The baseline analysis indicated that none of them were significant at the start of the study.

Conclusion

Based on the findings from this clinical trial involving patients undergoing benign hysterectomy, it was observed that the Maylard technique led to a significant increase in bleeding during surgery compared to the Cherney technique. However, the pain intensity experienced in the initial 3 days post-surgery was higher with the Cherney incision than with the Maylard incision. The duration from skin incision to entry into the abdominal cavity and the overall surgery time showed no significant differences between the two incision methods. No complications were noted with either technique. This indicates that both the Maylard and Cherney incisions can be safely utilized in women's surgeries, providing excellent exposure of the pelvic floor without any notable complications.