REVIEW ARTICLE
Year : 2022 | Volume
: 5 | Issue : 4 | Page : 159--164
Current status of inguinal hernia management: A review
Patrick J McBee1, Ryan W Walters2, Robert J Fitzgibbons1,
1 Department of Surgery, Creighton University School of Medicine, Omaha, NE, USA
2 Department of Clinical Research, Creighton University School of Medicine, Omaha, NE, USA
Correspondence Address:
Robert J Fitzgibbons
Department of Surgery, Creighton University School of Medicine, Creighton University Education Building, 7710 Mercy Road, Suite 501, Omaha, Nebraska 68124-2368
USA
Abstract
Groin hernias are the most common reason for primary care physicians to refer patients for surgical management. Patients often present with a bulge in the groin that is associated with pain in two-thirds of cases. Diagnosis is usually clinical, with physical exam and history being sufficient enough to confirm diagnosis without imaging. Groin hernias may be associated with morbidity and can become complicated by incarceration or strangulation, requiring emergent surgical repair. However, the risk of strangulation is sufficiently low in asymptomatic or minimally symptomatic patients with inguinal hernias that an initial approach of watchful waiting is safe and appropriate. Chronic pain and hernia recurrence are other potential complications that support a watchful waiting approach in asymptomatic patients. Patients with symptomatic hernias should be offered surgical repair. The objective of this paper is to review the current status of the clinical diagnosis and management of patients with inguinal hernias.
How to cite this article:
McBee PJ, Walters RW, Fitzgibbons RJ. Current status of inguinal hernia management: A review.Int J Abdom Wall Hernia Surg 2022;5:159-164
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How to cite this URL:
McBee PJ, Walters RW, Fitzgibbons RJ. Current status of inguinal hernia management: A review. Int J Abdom Wall Hernia Surg [serial online] 2022 [cited 2023 Mar 24 ];5:159-164
Available from: http://www.herniasurgeryjournal.org/text.asp?2022/5/4/159/365088 |
Full Text
Introduction
Attempts to successfully manage groin hernias date back to the earliest civilizations. The Egyptian tomb of Ankh-ma-Hor at Saqqara circa 2500 BC includes an image of a possible groin hernia repair.[1] The term “hernia” is derived from the Latin word “bud” or “offshoot,” and the condition is due to an organ protruding through the body cavity that normally contains it. In 1562, Gabrielle Falloppio first described the inguinal ligament and established the landmark as an integral component of groin hernia repair.[2] Hesselbach described the triangle that bears his name in 1816, further clarifying the anatomy used to distinguish various hernias. The term “groin hernia” refers to three distinct types of hernias: indirect inguinal, direct inguinal, and femoral. The relationship to the inguinal ligament and inferior epigastric vessels defines them. Direct and indirect hernias are above the inguinal ligament; direct hernias present medial to the inferior epigastric vessels and protrude through the posterior wall of the inguinal canal, whereas indirect hernias present laterally and pass through the internal inguinal ring. Femoral hernias present below the inguinal ligament and medial to the femoral vessels.
Historically, operative management of a groin hernia was discouraged because of consistently poor results. However, in 1889, Bassini described a novel technique of suturing the transversalis fascia, transversus abdominis muscle, and internal oblique muscle (Bassini’s famous “triple layer”) to the inguinal ligament, drastically improving patients’ outcomes.[3] This pure tissue repair became the gold standard for groin hernia repair for most of the twentieth century. More than 70 modifications of Bassini’s tissue technique were subsequently described, with the multi-layer Shouldice repair perhaps being the most significant.[4] In 1984, Lichtenstein popularized an alternative “tension-free” prosthetic repair which involves the use of mesh to reinforce the posterior wall of the inguinal canal. Later, laparoscopic minimally invasive approaches (MISs) were introduced and resulted in faster recovery and decreased post-operative pain.[5] More recently, laparoscopic herniorrhaphy using robotic technology has become increasingly popular.[6]
Throughout the twentieth century, it was recommended that all groin hernias should be surgically repaired, regardless of whether the patient presented with symptoms or not as repair is the definitive treatment.[7] This recommendation was based on the assumption that groin hernias left untreated would inevitably result in an unacceptable rate of the life-threatening complications of bowel obstruction or strangulation. However, in 2006, an approach of “watchful waiting” emerged as a viable and safe option for patients who were asymptomatic or minimally symptomatic after Fitzgibbons demonstrated minimal risk of bowel obstruction or strangulation in this subset of patients.[8] This study only evaluated men, and extrapolation of findings to women with hernias cannot be made.
Epidemiology and Risk Factors
Groin hernias are the most common reason for primary care physicians to refer patients for surgical management; over 1.6 million groin hernias are diagnosed in the USA annually, with an incidence of 315 per 100,000.[9] Moreover, more than 500,000 groin hernias are surgically repaired each year with 217 per 100,000 of the population undergoing hernia repair annually.[9],[10] The prevalence of hernia repair increases with age with 0.25% of patients 18 years of age to 4.2% in patients 75–80 years of age undergoing repair.[11],[12] In the US, inguinal hernias comprise 97% of groin hernia repairs (90.2% males, 9.8% females) and femoral hernias comprise 3% of groin hernia repairs (29.8% males, 70.2% females).[11]
Well-established risk factors for the development of inguinal hernias include male sex, increased age, and genetic predisposition.[11],[13] Groin hernias are significantly more common in men as lifetime risk of groin hernia is an estimated 27% in men compared with 3% in women.[9] Femoral hernias are more common in women compared to men on a percentile basis, but women with a clinical groin hernia are still five times more likely to have an inguinal hernia than a femoral hernia.[14] The risk of hernia development in general gradually increases with age with a bimodal spike in prevalence in the children less than 5 years of age and men greater than 75 years of age.[11] A genetic predisposition to developing inguinal hernia exists as well; having a first degree relative with an inguinal hernia increases the risk of developing a hernia.[15] Other factors that have been reported to potentially increase risk include smoking, chronic obstructive pulmonary disease, lower body mass index, high intrabdominal pressure, thoracic or abdominal aortic aneurysm, patent processes vaginalis, history of open appendectomy, peritoneal dialysis, and collagen vascular disease.[16]
Clinical Presentation and Diagnosis
Patients typically present with a bulge in the groin that is associated with pain in two-thirds of cases.[17] Painful hernias are most frequently described as a dull aching, heavy, dragging, or burning sensation. Maneuvers that increase intra-abdominal pressure, such as straining, lifting, or coughing, may exacerbate pain or hernia size by causing intra-abdominal contents to be pushed through the fascial defect.[18] Some patients may complain of worsening symptoms at the end of the day or after increased activity. Minor symptomatic cases may be temporarily improved by lying down or reducing the hernia manually. Severe or unbearable pain, that is, sudden onset, suggests possible strangulation and should be treated as an emergency.
Inguinal hernias are primarily diagnosed by history and physical examination with secondary imaging rarely needed.[19] Some patients with a clinical history suggestive of a hernia with no physical findings may need additional imaging studies to rule in or rule out the diagnosis. Visual examination should be performed first, by having the patient stand as the physician inspects for a visible bulge while seated in front of the patient. If needed, the patient should be directed to perform a Valsalva maneuver to promote hernia visibility. If no visible bulge is present, the physician may palpate the base of the scrotum or labia majora toward the pubic tubercle using the index finger.[20] The goal is to insert the index finger into the external ring, and upon the patient performing a Valsalva maneuver, a soft impulse may be appreciated.[20] Imaging with non-contrast magnetic resonance imaging (MRI) or computed tomography (CT) with Valsalva is recommended for diagnosing groin hernias when physical examination is insufficient.[21] Ultrasound (US) is less expensive but is highly dependent on the expertise of the examiner.[21] The sensitivity values for MRI, CT, and US are 0.91, 0.77, and 0.56, respectively. Whereas the specificity values of MRI, CT, and US are 0.92, 0.25, and 0, respectively.
Management
Watchful waiting
Management of inguinal hernias has evolved over time to improve patient safety and quality of life. Recent evidence from three randomized control trials established that for patients who present asymptomatically or minimally symptomatic and do not wish to undergo elective hernia repair, a conservative approach of “watchful waiting” is a safe alternative.[8],[22],[23][Table 1] and [Table 2] illustrate the significant comparisons and findings across all watchful waiting clinical trials. This has become especially important as surgeons and patients have begun to appreciate the problem of post-herniorrhaphy groin pain which occurs in a small percentage of patients undergoing an inguinal hernia repair. It is mild in most patients but may become incapacitating in some. When one puts this into perspective with other possible complications of an inguinal herniorrhaphy such as hemorrhage, infection, recurrence, and so forth, watchful waiting becomes an attractive alternative. Unfortunately, long-term follow-up of the watchful waiting trials has found that most patients, up to 68%, who do not elect to undergo immediate hernia repair will eventually be treated surgically due to worsening pain or lifestyle limitations from progression. Although it is safe to delay surgery for patients with asymptomatic or minimally symptomatic inguinal hernia, eventual surgical intervention is nearly inevitable if the patient lives long enough.[24]{Table 1} {Table 2}
Surgical Treatment
Patients who present with a bowel obstruction or signs of strangulation (extremely tender groin mass and signs of sepsis, e.g., fever, tachycardia, hypotension, emesis, and confusion) due to their groin hernias require emergency surgery. Watchful waiting is not an appropriate treatment option for any patient with painful, symptomatic groin hernias. Patients with significant lifestyle limitations, such as reduced mobility, due to pain or other factors should be offered operative repair to improve their quality of life. It should be noted that incarceration is not synonymous with strangulation, nor will it inevitably lead to strangulation, as many patients with chronically incarcerated groin hernias are asymptomatic. Hernia repair is performed either as an open (tissue- or mesh-based) procedure or a minimally invasive (laparoscopic or robotic) procedure.
The choice of which procedure is performed is most often based on surgeon expertise and access to resources, rather than patient factors.[25] Evidence-based practice guidelines recommend a tailored approach to inguinal hernia management based on the individual patient. For example, the guidelines recommend an MIS to bilateral inguinal hernia or recurrent inguinal hernia that was previously repaired with open surgery, thereby repairing both hernias in one operation, instead of two separate interventions.[26] Despite guidelines, however, it is estimated that only 42% of surgeons offer an MIS to this patient population.[27] Multiple factors influence which operative approach is performed, including the surgeon’s characteristics of age, practice type, and location. Patient factors that inform choice of approach include overall health, hernia characteristics, and type of original repair for recurrent hernias. One study interviewed surgeons to investigate other individual factors that led to practices outside of recommended guidelines, finding that access and resources, namely, the surgeon’s opportunity to operate on the robot at their institution, were significant factors that influenced approach as well.[25]
Open approach
The open repair with mesh (Lichtenstein tension-free) technique is the current gold standard of care for most patients with an inguinal hernia.[26] The use of prosthetic mesh is recommended because of its association with a 50%-75% lower risk of hernia recurrence, lower risk of chronic pain post-operatively, and an earlier return to work compared with a sutured repair.[28] The tissue (sutured) repair is performed in limited circumstances, most often when mesh is contraindicated, such as potential infection from a contaminated field. Among non-mesh open repairs, the Shouldice technique is recommended due to its lower risk of recurrence compared with other pure tissue repairs (e.g., McVay or Bassini techniques).[28] The recurrence rate with the Shouldice techniques is higher than that with the mesh techniques [odds ratio (OR) 3.80, 95% confidence interval (CI) 1.99–7.26] but lower than other pure tissue repairs (OR 0.62, 95% CI 0.45–0.85).[29] The best results with the Shouldice procedure are seen in specialty clinics such as the Shouldice in Toronto, but are not reproduced in general practice.[30] A detailed discussion of other unique specialty tissue repairs such as the Onstep or the Desarda method are beyond the scope of this manuscript.
Minimally invasive approach (MIS)
Groin hernias can be repaired using laparoscopic techniques. Most often, the principle is to perform the repair in the preperitoneal space which is behind the muscular elements of the groin as opposed to the open approach which is performed anteriorly, referred to as a transabdominal preperitoneal (TAP) approach. A totally extraperitoneal approach (TEP) is also performed, with the potential advantage of avoiding intra-abdominal access through the peritoneum.
Open vs. minimally invasive
The outcomes of patients who have undergone open or minimally invasive inguinal repairs have been widely studied. A meta-analysis performed in 2019 reported on 16 trials including over 51,000 patients that compared open, TAPP, TEP, and robotic preperitoneal inguinal hernia repairs (rTAPP).[31] Ultimately, the study showed that all modalities were comparable in the short term. Among the trials, 35.5% underwent open, 33.5% TAPP, 30.7% TEP, and 0.3% rTAPP repairs.
The post-operative chronic pain RR was similar for TAPP vs. open (RR 0.53; 95% CrI 0.27–1.20), TEP vs. open (RR 0.86; 95% CrI 0.48–1.16), and TEP vs. TAPP (RR 1.70; 95% CrI 0.63–3.20). The recurrence RR was comparable when comparing TAPP vs. open (RR 0.96; 95% CrI 0.57–1.51), TEP vs. open (RR 1.0; 95% CrI 0.65–1.61), TEP vs. TAPP (RR 1.10; 95% CrI 0.63–2.10), and rTAPP vs. open (RR 0.98; 95% CrI 0.45–2.10). No differences were found in terms of post-operative hematoma, surgical site infection, urinary retention, and hospital length of stay. The authors concluded that the choice of the most suitable treatment should be based on individual surgeon expertise and tailored on each patient.
The chance of developing post-operative groin pain following hernia repair is an important point to discuss with patients before proceeding with surgery. It is reported that chronic post-operative is evident in approximately 8%-16% of the patients, without consideration of the surgical approach.[32],[33] Overall, it appears that MISs most likely result in less groin pain than open procedures. A meta-analysis completed in 2019 that evaluated 12 randomized trials and nearly 4,000 patients found that laparoscopic repair was associated with a reduced rate of acute pain compared with open repair (mean difference 1.19, CI -1.86, -0.51, P ≤ 0.0006) and reduced odds of chronic pain compared with open (OR 0.41, CI 0.30–0.56, P ≤ 0.00001).[34] The authors clearly addressed, however, that the trials were of variable methodological quality.
It is commonly believed that open inguinal hernia repair is thought to cause worse post-operative pain than minimally invasive surgery, and thus patients are often prescribed more opioids at discharge. One study investigated opioid use after surgery with open and MIS techniques.[35] The authors conducted a survey of 250 opioid naive hernia patients and converted opioid prescription doses into morphine equivalents, comparing opioid use across groups after surgery. Overall, there was no difference in opioid use by approach [open 15 (IQR 0, 60) morphine milligram equivalents vs. 9 (IQR 0, 50) minimally invasive surgery; P = 0.33]. More than one-third of patients used no opioids (open 38% vs. minimally invasive surgery 44%; P = 0.42). Bilateral repair was not associated with increased opioid use (univariate odds ratio 1.23, P = 0.58). Ultimately, the authors concluded that post-discharge opioid utilization was clinically similar between patients undergoing open and minimally invasive surgery inguinal hernia repair and those requiring unilateral or bilateral repair. They also suggested that 0–8 tablets of 5 mg oxycodone are sufficient for most opioid-naive patients undergoing inguinal hernia repair.
Most authorities agree that a minimally invasive procedure should be recommended for patients with bilateral inguinal hernias because both can be repaired through the same three minimal access ports, avoiding the need for bilateral groin incisions. A recurrent hernia after an open inguinal herniorrhaphy failure should also be repaired by an MIS method, as long as there are no contraindications to laparoscopy, e.g., severe adhesion, inability to tolerate general anesthesia, and so on.
Groin hernias in women
There is a paucity of data that investigates groin hernia outcomes in women; significant investigational efforts clearly remain. Some authors have reported the rate of emergency procedures in women, 14.5%-17.0%, is 3–4-fold higher than that in men.[36] Watchful waiting is not appropriate in women because of the increased incidence of hernia strangulation and difficulty in distinguishing inguinal from femoral hernias.[14] Thus, surgical repair is routinely recommended for non-pregnant women with groin hernias.[26] Pregnant women with a groin bulge which appears to be a hernia should have round ligament varicosities ruled out by ultrasound before considering surgery.[26]
Economic Data
Recent economic data assessing the impact of watchful waiting on costs to the patient and hospital are lacking. Initially after Fitzgibbons published the US trial in 2006 describing watchful waiting as a safe alternative for asymptomatic inguinal hernia patients, Stroupe et al.[37] assessed the economic data from the trial and reported that conservative treatment with watchful waiting is also a responsible approach from a standpoint of cost-effectiveness. The authors used Medicare payment rates to estimate the costs of inpatient and outpatient care from the healthcare payer’s perspective. The surgical repair group exhibited a marginally higher cost of $1,831 compared with the watchful waiting group at 2 years of follow-up ($7,875 vs. $6,044). Additionally, the quality-adjusted life year (QALY) for the surgical repair group (1.724) was slightly higher than that of the watchful waiting group (1.693) with a mean difference of 0.031 (0.001–0.058). However, the cost per QALY gained from assignment to the repair group was $59,065 (95% CI $1,358–$322,765) per patient. The authors concluded that both watchful waiting and immediate surgery for inguinal hernias were reasonable from a cost-effective standpoint.
Additional studies assessing the financial impact and cost-effectiveness of watchful waiting compared to surgical repair are warranted to further understand the economic consequence on stakeholders.
Conclusions
Inguinal hernias are a very common problem. Diagnosis is typically made from history and physical examination. Watchful waiting is a safe initial strategy for men with asymptomatic or minimally symptomatic inguinal hernias, though most patients will eventually undergo operative repair within 10 years due to increasing pain or lifestyle limitations. The risk of hernia incarceration or strangulation is sufficiently low, however, if watchful waiting is the preferred management. Operative management should also be offered to patients and is a safe procedure, although post-operative pain may develop in some cases.
Financial support and sponsorship
Nil.
Conflicts of interest
There are no conflicts of interest.
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