Discussing Michael Grabner's Injury and Surgery: What is a Sports Hernia?

A couple weeks ago, the New York Islanders announced that Austrian winger Michael Grabner would start the season on IR with an undisclosed lower-body injury. Grabner, known around the NHL for his speed, has battled some groin soreness over his career. It was revealed that Grabner had a "sports hernia" that required surgery and that he would be out indefinitely (*ignore the 4-6 weeks in the tweet below).

Sports hernia surgery successful for Michael Grabner. Just picked him up from hospital. Back in 4-6 weeks #Isles #NHL pic.twitter.com/A2xkCsOiR2
— Andy Strickland (@andystrickland) October 9, 2014

THE INJURY: WHAT IS A SPORTS HERNIA? 

One of the more frequent sports injuries that poses a difficult clinical problem is chronic groin pain in male athletes. Chronic exercise-related groin pain can present as a difficult diagnostic and therapeutic challenge. The condition 'sports hernia' was only recently described but is becoming an increasingly recognized source and cause of chronic groin pain. Sports hernia, sometimes known as athletic pubalgia, is a diagnosis which is poorly understood as there is little consensus in medical literature regarding pathophysiology, criteria for diagnosis, and treatment methods. 

Sports hernia as a diagnosis often goes unrecognized for several months or even years [1]. Athletes will often present with groin pain and be diagnoses with a 'groin strain,' receive light treatment and be recommended rest. In sports hernia, there actually is no classical herniation of soft tissue, and the diagnosis and treatment decision requires a team/multiprofessional approach consisting of general physicians, surgeons, radiologists and physiotherapists. 

The team approach is required due to the criteria required for a diagnosis of sports hernia. While still a poorly understood phenomenon, sports hernia is essentially a set of injuries to the abdominal and pelvic musculature that cause a weakness of the posterior wall of the inguinal canal [2]. The groin pain is "associated with an incipient direct bulge of the inguinal wall whenever the abdominal muscles contract forcefully" [3]. The minimum required criteria required for a diagnosis of a sports hernia include [4]:

• Chronic groin pain which develops during exercise 
• Pain is located over the lower lateral edge of the rectus abdominis muscle
• Radiation of pain to the testis or adductor longus origin (but not required)
• Pain is often aggravated by sudden acceleration, twisting and turning, cutting and kicking, sit-ups and coughing or sneezing
• Subtle but consistent physical examination findings 
• May or may not include; subtle bulges, pain due to resistance, tenderness, etc.
• Appropriate imaging characteristics. 

So, to obtain a diagnosis, all of these criteria must be simultaneously present due to the numerous other potential causes for groin pain, and the fact that these hernias have also been found to be asymptomatic in the general population [4]. 

SYMPTOMS

Chronic groin pain and sports hernia are often restricted or more common in sports that involve rapid acceleration along with a sudden change in direction (american football, ice hockey, soccer - in which kicking can also cause the injury).  Athletes with this injury often present with pain that is exacerbated with exercise in the regions shown in the image below:

Solid arrows indicates that the pain can sometimes radiate to the testis.
Dotted arrows show pain radiating into the medial thigh along the path of the adductor longus. [3]

Athletes will not only complain about pain occurring on exertion or certain movements, but also the pain persisting after activity with accompanying stiffness or tenderness. Some athletes believe the pain to be disabling to the pain of cessation from activity and the pain returning even after an extended period of rest. 

A physical examination will reveal tenderness over the affected region, and sometimes a skilled examiner will be able to feel a dilation or weakness in the inguinal canal area [5].  Physicians should test the athlete for pain with resisted sit-ups and resisted hip adduction and should also look for a restricted range of motion of the hip. One of the more important parts of the physical examination is ruling out other possibilities for groin pain and other injuries as shown below:

[5]

DIAGNOSIS

Imaging is one of the most useful diagnostic tools available for physicians when an athlete presents with chronic groin pain. However, a majority of the time, imaging techniques are  largely used as a method of ruling out other causes of groin pain (due to the overlapping symptoms between sports hernia and other sources of chronic groin pain) [5]. Two of the main imaging sources are ultrasound and magnetic resonance imaging (MRI). While these diagnostic tests are largely helpful and imaging protocols have improved over the years, physicians still rely heavily on the history and physical examination of a patient to make a diagnosis. Investigating chronic groin pain routinely involves several imaging examinations (radiographs & CT scans in addition to those shown below). just to rule out other potential causes such as pelvic instability, hip joint problems (which could be co-existing) including labral tears, bone stress, soft tissue calcifications, and finally supporting ligament damage.

There are two key imaging features that must be simultaneously present to support a clinical diagnosis. The first feature is an incipient direct bulge of the posterior inguinal wall when the patient forcefully contracts the abdominal muscles (for example when doing a sit-up). This feature is best seen during a real-time ultrasound as shown in the videos below.

Normal motion of the posterior inguinal wall from John Read on Vimeo.

The video above shows a normal pattern of inguinal wall motion. When the conjoint tendon becomes taught as internal oblique and transversus abdominis muscles contract, the superior wall of the inguinal canal normally moves inferiorly to protect agains herniation of abdominal contents [3]. 

This can be compared with the video below, showing an incipient direct bulge of the posterior inguinal wall on contraction of the same muscles (usually done by a half sit-up).

Sports hernia: Dynamics of the inguinal wall from John Read on Vimeo.

Here, the red line indicates the posterior inguinal wall which is initially concave at rest, but when strained, it displaces anteriorly as a convex bulge shown by the yellow arrow [3]. Although this bulge can have a variety of causes, when found together with a second imaging feature, it helps confirm the diagnosis of sports hernia.

That second key imaging feature is a demonstrably abnormal conjoint tendon, normally very subtle on imaging exams. Shown below is an MRI of a left conjoint tendon demonstrating this 'tendonitis.' 

MRI of left conjoint tendon [3]

TREATMENT

Non-operative
Non-operative management of sports hernias and chronic athletic groin pain consists of a combination of; rest, non-steroidal anti-inflammatory drugs (NSAIDs), corticosteroid injections, and physiotherapy. Usually, non-operative treatment is the first plan for patients presenting with the symptoms consistent with a diagnosis of sports hernia and can last a period of between 6-12 weeks [6]. One of the most important parts of physiotherapy is core strengthening exercises that target the abdomen, lumbar spine, and hips. These strengthening exercises combined with focused stretching exercises on the hip rotators, adductors, and hamstrings work together to try and correct the imbalance of the hip and pelvic muscle stabilizers; a common source of groin pain. 

While a small subset of patients will improve with rehabilitation and non-operative treatment, the large majority of patients that have been accurately diagnosed with sports hernias will eventually require surgical repair. In fact, some experts argue that if the pain from a groin injury does not improve within 4 to 6 weeks after diagnosis, the athlete is at increased risk of developing chronic inguinal pain [7].

Surgery 
The primary goal of operative management is reinforcing the posterior abdominal. Two main techniques include:

• Open surgical techniques (Bassini, Shouldice, Lichtenstein) aim to reinforce the abdominal muscles or fascia near the inguinal ligament.
• Laparoscopic repair (preferred to open) which involves reinforcement of the posterior abdominal wall with mesh. 

Both techniques have produced successful results and success rates (return to full athletic activity) have been reported as 92.8% for open techniques and 96% for laparoscopic techniques [6]. 

In a clinical trial of 60 patients with sports hernia, it was indicated that surgical treatment was more efficient and effective than conservative, non-operative therapy. The study randomized 30 athletes with similar characteristics and pain scores into two treatment groups (one received non-operative treatment, the other received surgery) and followed them for 12 months. 27/30 who received the operation returned to sports activities after 3 months, compared with 8/30 in the non-operative treatment group. Of the 30 athletes in the conservative treatment group, 7 (23%) eventually elected to undergo surgery due to persistent groin pain. [8]

In 2003, Dr. Muschaweck and Dr. Berger developed an innovated open suture repair (Minimal Repair technique) to fit the needs of professional athletes [7]. The surgical intervention aims to eliminate groin pain by decompression of the genital branch of the genitofemoral nerve. The surgery stabilizes the posterior wall via a tension-free suture through a minimally-invasive procedure (minimal dissection). After a small inguinal incision and dissection of subcutaneous tissue, the repair beings and is demonstrated via the figures below.

 

In comparison with the aforementioned commonly-used surgical procedures (open repairs and laparoscopic repairs), the Minimal Repair technique presented here has several advantages including: no insertion of prosthetic mesh, no general anesthesia use, less traumatization, lower risk of complication, equivalent and sometimes quicker recovery [7]. Avoiding mesh is key especially for athletes who require full elasticity and movement. Mesh can result in localized stiffening, leading to restricted movement of the abdominal muscles. Additionally, mesh can sometimes be prone to complications such as infections and fistula formation (which requires removal of the mesh) along with mesh migration.

RECOVERY

Much like the non-operative management, post-operative treatment involves conventional non-steroidal anti-inflammatory drug (NSAID) use along with physiotherapy. Safe progression through the various stages of a rehabilitation program are key towards a full recovery. The main goals of rehab include [4]:

• Minimizing pre-existing risk factors
• Implementing core stabilization exercises 
• Maintaining good motor control and strength around the pelvis. 

Recovery after laparoscopic repair generally takes 6-8 weeks before full return to play is permitted. This can range from 4-12 weeks in the extreme. Post-surgical recovery times for open surgeries was found to be an average of 17.7 weeks compared to the average of 6.1 weeks for laparoscopic repairs [6]. 

On the other hand, the minimal repair technique described above reported that 124/129 patients resumed training in 4 weeks time while 75.8% of those 129 reported a full return to pre-injury sports activity levels at the 4 week mark.

In a study of 43 NHL players who were reported to have a sports hernia and who underwent surgery from 2001-2008, 80% ultimately returned to play 2 or more full seasons [9]. Players were split into two groups, one group with players with 6 or fewer seasons of play, and another consisting of players with 7 or more years of play [in the NHL]. Players with over 7 full seasons returned but with significant  decreases in their overall performance levels while players with 6 or fewer seasons were able to return to play without any statistical decrease in performance. While the decrease in play could be based on a natural decline seen across the board with NHL players, the surgery was definitely a factor. Results can be seen below: 

[9] Study shows that players who undergo the surgery RTP and depending on veteran experience, may perform less than their pre-surgery level.

These results should be taken with a grain of salt. Many of these injuries, and subsequently their repairs, occurred years ago and in the time that has passed (close to 6 years) methods and rehab techniques have improved. Unfortunately, this study did not obtain the average time to recovery for NHL players.

CONCLUSION 

Sports hernia is a difficult injury to both diagnosis and manage. The process is long:

[1]

Diagnosis requires a high index of suspicion, a multidisciplinary approach and a plan for recovery. Surgery has proven to be the best method and recent innovations have made returning from the injury much quicker and easier. Recent advances in imaging, techniques and understanding the underlying causes and pathophysiology of sports hernia has led to improved clinical outcomes and a shorter recovery time.

Sources

1. Brown A, Abrahams S, Remedios D, Chadwick S. Sports Hernia: a clinical update. Br J Gen Pract 2013; DOI: 10.3399/bjgp13X664432
2. Meyers WC, McKechnie A, Philippon MJ, et al. Experience with 'sports hernia' spanning two decades. Ann Surg 2008; 248(4): 656-665. 
3. Dr. John Read, Sports Medicine Imagine: Sports Hernia. http://www.sportsmedicineimaging.com/topics/sports-hernia/
4. Garvey JFW, Read JW, Turner A. Sportsman hernia: what can we do? Hernia 2010; 14: 17-25. 
5. Minnich J, Hanks J, Muschaweck U, Brunt LM, Diduch DR. Sports Hernia: Diagnosis and Treatment Highlighting a Minimal Repair Surgical Technique. Am J Sports Med 2011; 39(6): 1341-1349. 
6. Caudill P, Nyland J, Smith C, et al. Sports hernias: a systematic literature review. Br J Sports Med 2008; 42(12): 954-964.
7. Muschaweck U, Berger L. Sportsmen's groin - diagnostic approach and treatment with the minimal repair technique: a single center uncontrolled clinical review. Sports Health 2010; 2: 216-221. 
8. Paajanen H, Brinck T, Hermunen H, Airo I. Laparoscopic surgery for chronic groin pain in athletes is more effective than nonoperative treatment: A randomized clinical trial with magnetic resonance imaging of 60 patients with sportsman's hernia (athletic pubalgia). Surgery 2011; 150(1): 99-107. 
9. Jakoi A, O'Neill C, Damsgaard C, Fehring K, Tom J. Sports Hernia in National Hockey League Players: Does Surgery Affect Performance? Am J Sports Med 2013; 41(1): 107-110. 

Updated for grammatical errors and to include more information about recovery times.