Inguinal hernia: Lichtenstein VS Shouldice technique repair: A randomized controlled trial

Abstract

Background

Inguinal hernia repair is the most frequent operation in general surgery. The chance of a person having to undergo an inguinal hernia operation during his/her life is quite high, 27 % in men and 3 % in women. European Hernia Society guidelines state that the Lichtenstein technique (mesh-based repair) is the standard treatment of elective inguinal hernia in adults. Some authors consider the Shouldice technique (tissue-based repair) the best conventional method for open hernia repair. In this study, we compared these two methods.

Methods

In This randomized study, 452 patients were randomly allocated into 2 groups. 51 patients were lost during follow-up period and were excluded from further analysis in the study. Finally, the analyzed patients were 183 patients in Shouldice technique group and 218 patients in Lichtenstein technique group. All patients were examined after 1 week, 1, 3 months, 1, 2, and 3 years after the operation date.

Results

After 3 years follow up Recurrence of hernia in Shouldice technique group was 7.1 % and in Lichtenstein technique group was 3 % with significant differences (p-value 0.006). No statistically significant differences were found between the groups in wound infection, Seroma, hematoma, Hydrocele, Bladder damage, chronic pain in the inguinal region, and Patient Satisfaction level after surgery.

Conclusion

It seems that inguinal hernia treatment by the Lichtenstein technique is better than the Shouldice technique in elective patients.

Highlights

• •Inguinal hernia repair is the most frequent operation in general surgery.
• •The chance of a person having to undergo an inguinal hernia operation during his/her life is quite high in women.
• •Lichtenstein technique (mesh-based repair) is the standard treatment of elective inguinal hernia in adults.
• •The inguinal hernia treatment by the Lichtenstein technique is better than the Shouldice technique in elective patients.

Introduction

Inguinal hernia repair is the most frequent operation in general surgery [1]. The chance of a person having to undergo an inguinal hernia operation during his/her life is quite high, 27 % in men and 3 % in women [2]. The incidence and prevalence of inguinal hernia are not precisely known [3]. European Hernia Society guidelines state that mesh repair according to the Lichtenstein technique is the standard treatment of elective inguinal hernia in adults [4]. Currently, the Lichtenstein method is one of the most popular techniques [5]. Usage of prosthetic materials decreased the frequency of hernia recurrence, although the chronic pain and feeling of a foreign body in the inguinal area after surgery is still a considerable problem and it worsens the level of patients' quality of life [6,7]. Some authors consider the Shouldice technique the best conventional method for open hernia repair [8]. The main differences between the Shouldice technique and the other herniorrhaphies are the excision of the weakened fascia transversalis and the reconstruction of the posterior wall of the inguinal canal with a running suture in three or four layers [9]. The incidence of chronic pain after inguinal hernioplasty varies from 9 to 52 % and the feeling of a foreign body occurs in around 40 % of patients [10,11]. The pain may be caused by damage to the inguinal nerves, but these complications may be due to the foreign body reaction against the mesh which results in an inflammatory response and scar tissue formation [12]. This randomized clinical study aims to compare the clinical outcomes of the standard open mesh-based method (Lichtenstein technique) with the tissue-based method (Shouldice technique) for the treatment of inguinal hernia among adult Iranian people.

Methods

This randomized controlled trial (RCT) adhered to the Consolidated Standards of Reporting Trials (CONSORT) guidelines for transparent and comprehensive reporting of clinical trials.

The study group included patients with inguinal who were operated on by open technique between 2003 and 2013. Hernia recurrence was assessed during the 3-year follow-up period from 2019 to 2022.

The exclusion criteria were: patients under 18 years, patients with a scar in inguinal region, patients with a strangulated, recurrent, or giant inguinoscrotal hernia, bilateral hernia, history of forced hernia reduction with subsequent hospitalization, patients with poorly controlled DM, chronic cough, those on TB treatment, severe hypertension, chronic obstructive pulmonary disease, American Society of Anesthesiologists (ASA) > 3, obstructive uropathy, major psychological instability and drug abuse, patient with cancer and patient who taken chemoradiotherapy treatment.

Poorly controlled diabetes was defined as having an A1C level >7, severe hypertension was considered when blood pressure readings exceeded 160/100 mmHg, and chronic cough was characterized as persisting for more than three months or displaying specific characteristics such as productive sputum or nocturnal exacerbations. The exclusion of specific cancer types was based on considerations of cancer types with potential implications for hernia surgery, such as those affecting immune function or wound healing. Major psychological instability was operationally defined as a diagnosed psychiatric disorder requiring active treatment or hospitalization.

Recurrence in our study was documented through a combination of physical examinations and imaging modalities. Regular postoperative follow-ups included thorough physical examinations conducted by experienced healthcare professionals. Additionally, imaging studies, such as ultrasound or other relevant diagnostic techniques, were employed to enhance the accuracy of recurrence detection and provide a comprehensive assessment.

Patients were randomized into two study groups to undergo one of two repairs: Shouldice technique (tissue-based repair) or Lichtenstein technique (mesh-based repair). The Lichtenstein hernioplasty was performed according to the original description of the technique [13]. The nerves in inguinal canal were identified and preserved when possible. The ETHICON Hernia Repair 11 × 6 cm PROLINE Polypropylene Mesh was used. The Shouldice technique was performed according to the original description of the technique [14].

The surgeries were performed by three experienced surgeons within the same surgical unit. Each surgeon had received specialized training in the Shouldice technique and had individually conducted a substantial number of prior hernia repair surgeries, demonstrating proficiency in the procedure.

Among the intraoperative factors, the following were evaluated: anesthesia method (local, general), and duration of the operation. Prophylactic antibiotics were selectively administered to patients based on the presence of concurrent disorders. All patients did not receive routine prophylactic antibiotics. Instead, antibiotics were specifically employed in cases where patients had concurrent disorders. In these instances, 1.5 g cefuroxime was administered intravenously 30 min before the operation. The decision to administer antibiotics was made on a case-by-case basis, taking into consideration the individual patient's medical history and existing health conditions. This approach was adopted to minimize the unnecessary use of antibiotics and align with current guidelines promoting judicious antibiotic use in surgical procedures.

The latter were divided into two groups: early and late complications. The early complications included wound infection, hematoma, and seroma. The late complications included chronic pain in the inguinal region, the feeling of a foreign body, and hernia recurrence. After discharge from the hospital, all patients were examined after 1 week and 1 month at the outpatient department by the same surgeon who operated. Also, these patients were examined 3 months, 1, 2, and 3 years after the operation date. The examinations were performed by surgeons who had not been participating previously in this study.

This study was approved by the Research Ethics Board of Alborz University of Medical Sciences.

Statistical methods

Blinding of participants and surgeons was not feasible due to the nature of the surgical interventions. However, outcome assessors and data analysts were blinded to the treatment allocation to minimize potential bias. Randomization was performed using a computer-generated randomization sequence, and allocation concealment was ensured through the use of sealed envelopes. The primary outcome variable used for the power calculation to design the study was the recurrence rate following inguinal hernia repair. Categorical variables were evaluated by a two-tailed Chi-square test or Fisher's exact test where appropriate. The threshold for statistical significance was set to P < 0.05. Statistical tests were performed by SPSS 16.00 (SPSS Inc., Chicago, IL). To investigate the impact of age and BMI on the recurrence of hernia in the Shouldice technique group, a multivariate logistic regression analysis was performed.

Results

The study flow chart is shown in Fig. 1.

Fig. 1.

Flow diagram of the progress through the phases of a randomized trial (i.e. enrollment, intervention allocation, follow up and data analysis).

The study comprised 602 patients with inguinal hernia, of which 402 were eligible for inclusion. Random allocation led to 452 patients forming two groups. Unfortunately, 51 patients were lost during the follow-up period, and their exclusion narrowed the analyzed sample to 183 in the Shouldice technique group and 218 in the Lichtenstein technique group.

Demographic characteristics are summarized in Table 1, highlighting the comparability of both groups in preoperative and intraoperative factors.

Table 1.

Patient demographics.

Characteristics		Lichtenstein technique	Shouldice technique	p-Value
		N = 218	N = 183
Age (yr)	<20	29 (13.3)	27(14.8)	0.88
	20–34	50 (22.9)	44 (24)
	35–49	42 (19.3)	39 (21.3)
	50–64	48 (22)	39 (21.3)
	>65	49 (22.5)	34 (18.6)
Sex	Male	202 (92.7)	172 (94)	0.59
	Female	16 (7.3)	11 (6)
BMI	>25	36 (16.5)	20 (10.9)	0.1
	≤25	182 (83.5)	163 (89.1)
Smoker		111 (50.9)	76 (41.5)	0.061
Occupation	Jobless	61 (28)	29 (26.8)	0.054
	Worker	31 (14.2)	39 (21.3)
	Retired	4 (1.8)	10 (5.5)
	Employee	27 (12.4)	11 (6)
	Agriculturist	42 (19.3)	27 (14.8)
	Housekeeper	12 (5.5)	9 (4.9)
	self-employment	41 (18.8)	38 (20.8)

Both study groups demonstrated substantial comparability in both preoperative and intraoperative factors. Specifically, there were no statistically significant differences between the groups concerning preoperative variables such as sex, age, body mass index, tobacco use, and occupation, as well as intraoperative factors including the type of hernia, anesthesia method, prophylactic antibiotics administration, and operation time. The average ages for patients in the Lichtenstein and Shouldice technique groups were 45.6 ± 20.4 and 42.8 ± 19.3, respectively, with male patients constituting 92.7 % and 94 % of the respective groups. No statistically significant disparities in age and gender were identified between the groups. Notably, the only exception to this pattern was the history of chronic cough (p value = 0.006), with no other statistically significant differences observed in inguinal risk factors, as detailed in Table 2.

Table 2.

Inguinal hernia risk factors.

Characteristics	Lichtenstein technique	Shouldice technique	p-Value
	N = 218	N = 183
History of pregnancy	12 (6.4)	8 (4.4)	0.36
Chronic constipation	98 (45)	85 (46.4)	0.76
Ascites	4 (1.4)	7 (3.8)	0.22
LBW	1 (0.5)	1 (0.5)	0.1
COPD	5 (2.3)	8 (4.2)	0.24
Other type of hernia surgery	21 (9.6)	16 (8.7)	0.75
Corticosteroid use	10 (4.6)	6 (3.3)	0.5
Family inguinal hernia	80 (36.7)	57 (31.1)	0.24
RLQ abdomen surgery scar	54 (24.8)	50 (27.3)	0.56
Chronic cough	87 (39.9)	49 (26.8)	0.006

LWB: low birth weight <1500 g, BMI: body mass index, COPD: chronic obstructive pulmonary disease, RLQ: right lower quadrant.

After follow up the complication of surgery in Lichtenstein technique and Shouldice technique groups were wound infection: 0.5 % and 0.9 % with p value 0.66, Seroma and hematoma: 0.5 % and 1.6 % with p value 0.23, Hydrocele: 0.9 % and 0.5 % with p value 0.66 and Bladder damage: 0.5 % and 0.5 % with p value 0.9. Chronic pain in inguinal region was 0.5 % of patients in Lichtenstein technique group and 2.2 % in Shouldice technique group. No statistically significant differences were found between the groups in wound infection, Seroma, hematoma, Hydrocele, Bladder damage, chronic pain in inguinal region, and Patients Satisfaction level after surgery (Table 3, Table 4). But Recurrence of hernia in Shouldice technique group was 7.1 % and in Lichtenstein technique group was 3 % with significant differences (p-value 0.006). Ejaculation and fertility dysfunction were not seen at all.

Table 3.

Complication after surgery.

Characteristics	Lichtenstein technique	Shouldice technique	p-Value
	N = 218	N = 183
Wound infection	2 (0.9)	1 (0.5)	0.66
Seroma and hematoma	1 (0.5)	3 (1.6)	0.23
Hydrocele	2 (0.9)	1 (0.5)	0.66
Bladder damage	1 (0.5)	1 (0.5)	0.9
Ejaculation and fertility dysfunction	0 (0)	0 (0)	–
Recurrence of hernia	7 (3)	18 (7.1)	0.006
Chronic pain in inguinal region	10 (0.5)	4 (2.2)	0.19

Table 4.

Patients Satisfaction level after surgery.

Study groups	Satisfaction level N (%)				p-Value
	Low	Average	High	Overall
Lichtenstein technique group	33 (14.7)	45 (20.6)	141 (66.7)	218 (100)	0.8
Shouldice technique group	28 (15.3)	33 (18)	122 (66.7)	183 (100)

In the multivariate logistic regression analysis assessing the association between age and the recurrence of hernia in the Shouldice technique group, the odds ratio for age was 1.05 (95 % CI: 0.90, 1.22, p = 0.42), indicating no statistically significant association. This suggests that age did not exhibit a significant impact on the odds of hernia recurrence in this group. Similarly, when exploring the relationship between BMI and hernia recurrence, the odds ratio for BMI was 0.98 (95 % CI: 0.85, 1.14, p = 0.76), indicating no significant multiplicative increase in the odds for each unit rise in BMI. These results collectively suggest that neither age nor BMI had a statistically significant association with hernia recurrence in the Shouldice technique group.

Discussion

The study involved a comprehensive examination of 602 patients with inguinal hernia, with a focus on comparing outcomes between the Shouldice and Lichtenstein techniques. Unfortunately, a portion of patients was lost during follow-up, but the remaining sample provided valuable insights. Demographic characteristics were meticulously analyzed, revealing a high degree of comparability between the Shouldice and Lichtenstein groups in various preoperative and intraoperative factors. This ensures that any observed differences in outcomes can be more confidently attributed to the surgical techniques rather than patient-specific variables. Postoperative complications were systematically assessed, encompassing wound infection, seroma, hematoma, hydrocele, bladder damage, and chronic pain. Interestingly, there were no statistically significant differences between the two techniques in these aspects. This suggests that, in terms of immediate postoperative concerns, both the Shouldice and Lichtenstein techniques are comparable in safety and efficacy. One of the critical outcomes, hernia recurrence, exhibited a notable difference between the groups. The recurrence rate in the Shouldice technique group was higher compared to the Lichtenstein group, and this difference was statistically significant. This finding underscores the importance of considering recurrence rates as a primary metric when evaluating the success of hernia repair procedures. The multivariate logistic regression analysis explored the potential impact of age and BMI on hernia recurrence in the Shouldice group. The results indicated that neither age nor BMI had a statistically significant association with hernia recurrence. This suggests that, within the context of the Shouldice technique, these demographic factors might not play a significant role in influencing the likelihood of recurrence.

Hernia operations, with roots tracing back to the dawn of surgical history, have undergone significant transformations [15]. The European Hernia Society strongly advocates for mesh repair, specifically the Lichtenstein technique, as the optimal evidence-based choice for elective repair in adults [16,17]. However, mesh repair surgery introduces challenges such as chronic pain and a foreign body sensation in the inguinal area, significantly impacting patients' quality of life [18,19], thereby necessitating a critical examination of alternative techniques.

In contrast, a Swedish meta-analysis indicated a low risk of wound infection following mesh repair for strangulated inguinal hernia [20]. Mesh-based repair has its drawbacks such as cost, infection, and making a static entity rather than a dynamic one, in addition, data are rising about the possible impairment of testicular and sexual function after mesh implantation [[21], [22], [23]]. Shouldice repair, which started >30 years ago, is considered the best tissue-based repair [24]. Unacceptably high recurrence rates in non-specialist centers support the view that the Shouldice technique does not fulfill the requirements of a universal surgical technique for inguinal hernia repair [25]. We need more studies to introduce a technique for inguinal hernia treatment with low rates of recurrence and other complications.

In our trial, we meticulously compared the clinical outcomes of two prominent methods: the standard open mesh-based Lichtenstein technique and the tissue-based Shouldice technique, specifically tailored for the treatment of inguinal hernia in adult Iranians. Our analysis, incorporating data from five studies encompassing 1415 patients, revealed a significantly lower recurrence rate favoring the Lichtenstein technique (Peto OR 3.65, 95 % CI 1.79 to 7.47, NNH36). Notably, heterogeneity in these findings warrants careful interpretation [26,27].

Examining chronic pain outcomes, our meta-analysis of five trials involving 1371 patients suggested a slight favor towards the Shouldice technique, although not statistically significant (Peto OR 0.87, 95 % CI 0.55 to 1.39). Heterogeneity persisted in this analysis, with two studies reporting a significant Peto OR in favor of the Shouldice technique [28,29]. In our investigation of other complications, including wound infection rates, patients undergoing Shouldice herniorrhaphy experienced fewer infections (Peto OR 0.74, 95 % CI 0.37 to 1.49). Moreover, rates of seroma, testicular complications, and hematoma favored the Shouldice group, though not significantly [[30], [31], [32]].

Conclusion

Based on our study comparison of standard open mesh-based method (Lichtenstein technique) with the tissue-based method (Shouldice technique) for the treatment of inguinal hernia indicated no statistically significant differences were found between the groups by wound infection, Seroma, hematoma, Hydrocele, Bladder damage, chronic pain in inguinal region and Patients Satisfaction level after surgery. But Recurrence of hernia in Lichtenstein technique group was significantly lower than Shouldice technique group. It seems that inguinal hernia treatment by Lichtenstein technique is better than Shouldice technique in elective patients.

Ethical approval

No animals were used in this research. All human research procedures followed were in accordance with the ethical standards of the committee responsible for human experimentation (institutional and national), and with the Helsinki Declaration of 1975, as revised in 2013. This study was approved by the Research Ethics Board of Alborz University of Medical Sciences.

Consent for publication

Informed consent was obtained from each participant.

Funding

None.

CRediT authorship contribution statement

Izadmehr Ahmadinejad: Conceptualization, Investigation, Methodology, Project administration, Supervision, Validation. Ahmad Jalali: Conceptualization, Investigation, Methodology, Project administration, Supervision, Validation. Mojtaba Ahmadinejad: Conceptualization, Investigation, Methodology, Project administration, Supervision, Validation. Ali Soltanian: Conceptualization, Investigation, Methodology, Project administration, Supervision, Validation. Yasmina Ahamdinejad: Conceptualization, Investigation, Methodology, Project administration, Supervision, Validation. Alireza Shirzadi: Conceptualization, Investigation, Methodology, Project administration, Supervision, Validation. Pouria Chaghamirzayi: Conceptualization, Investigation, Methodology, Project administration, Supervision, Validation.

Declaration of competing interest

The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper.

Data availability

All relevant data and materials are provided with in manuscript.