Clinical Vignette of a Runner's Frustrating Groin Pain.

HISTORY AND PHYSICAL EXAMINATION A 45-yr-old healthy male runner presented with predominantly right lower abdominal, pelvic, and worsening groin pain that started 1 yr ago after completing a 22-mile run. His symptoms developed 3 wks after this last run. He was increasing his weekly mileage with a running coach to train for a full marathon. He did not have similar previous symptoms. He did not change his running style, shoe wear, or running surface. His pain was constant, sharp, throbbing, graded 5/10, and nonradiating. Pain worsened with prolonged running, quick transitions, coughing, and sneezing. For 6 mos, he stopped running and competing at races but gradually returned to running inconsistently for 10–15 mile/wk. He consulted an orthopedic sports surgeon who prescribed ibuprofen for 2 wks and physical therapy twice weekly for 3 mos, focusing on lumbopelvic stability, core strengthening, balance, and kinetic chain deficiencies, while cross training independently with biking. When he tried short intermittent runs after completing therapy, his pain worsened at the 5-mile mark. This strategy failed to provide significant pain relief or functional improvement. He did not try osteopathic/chiropractic manipulations, acupuncture, or electromechanical modalities. Given the persistent symptoms, he consulted a sports physiatrist. On examination, his vitals were stable, and he was well appearing. He had a nonantalgic gait with nontender lumbar paraspinal muscles, lower abdomen, pubic symphysis, hip flexors, and greater trochanters, but tenderness over right hip adductor origin. He had painless full range of motion at the lumbar spine/hips, except his right hip internal rotation was 15 versus 20 degrees on the left. His lower motor strength was 5/5 bilaterally, except right hip abductor was 4/5 and left side was 4+/5. Trendelenburg sign was seen with single-leg stance bilaterally. Resisted side-lying right hip adduction reproduced his symptoms mildly. Lower extremity sensation and reflexes were grossly intact bilaterally. Right FADIR (flexion, adduction, internal rotation) and Stinchfield tests reproduced his right midgroin pain. Patrick test, straight leg raise, and facet loading bilaterally were negative. Resisted sit-ups reproduced similar pains. A running/gait analysis suggested increasing his cadence to 180–200 steps/min (compared with 168 steps/min), shortening his stride length, changing from rear-foot to midfoot strike running pattern, increasing hip extension during swing phase, and improving pelvic control (pelvic drop and hip adduction noted during stance phase). He repeated physical therapy twice per week for 2–3 mos at a location experienced with runners to improve these findings. He also tried naproxen for 1 wk. This strategy did not improve his symptoms. What is your leading differential? DIFFERENTIAL DIAGNOSIS/POTENTIAL APPROACHES TO MANAGEMENT The differential diagnosis of groin/pelvic pain can be challenging because of the complex anatomy, multifactorial etiology, and poor consensus regarding nomenclature. It has been difficult to establish regional anatomic landmarks. In addition, older terminologies such as “sports hernia” and “inguinal disruption” have been replaced with newer terms such as “core muscle injury,” when it became clearer that no true hernia exists. The 2015 Doha agreement established four new groin pain subcategories: adductor-, inguinal-, pubic-, and iliopsoas-related groin pain.1,2 The most likely causes for groin/pelvic pain include athletic pubalgia or adductor muscle strains and tears. Other differentials are pubic ramus stress fractures or osteitis pubis, both causing low-intensity chronic pain, and femoroacetabular impingement, where pain refers to the groin/pelvis.1,3 Often overuse injuries are managed conservatively with activity modification, anti-inflammatory medications, physical therapy, and/or image-guided injections.1–3 Anatomic and metabolic differentials to rule out include appendicitis, inflammatory bowel diseases, urinary tract infections, nephrolithiasis, rectal/testicular pains, gynecologic disorders, pelvic floor dysfunction, lymphadenopathy, pelvic/femoral head/neck fractures, hip osteoarthritis, hip avascular necrosis, pediatric hip disorders, sacrotuberal ligament pains, sacroiliac joint dysfunction, internal snapping hip syndrome, piriformis syndrome, obturator neuropathy, lumbosacral radiculopathy, greater trochanter/iliopsoas muscle bursopathies, and inguinal hernia.1,4–6 Surgery is considered if conservative management fails. With orthobiologic medicine techniques, such as ultrasound-guided prolotherapy, platelet-rich plasma injections, mesenchymal stem cell therapies, and percutaneous needle tenotomy (PNT), patients have options to try before surgical intervention. What tests help elucidate the diagnosis? DIAGNOSTIC RESULTS On limited abdominal/pelvic ultrasound, no inguinal hernia was identified. An x-ray of the pelvis/bilateral hips showed preserved hip joint spaces, normal pubic symphysis, and sacroiliac joints. A pelvic magnetic resonance imaging (Fig. 1) revealed bilateral adductor longus tendon partial tears at the pubic origins, which are also known as “secondary cleft signs,”7 left mildly greater than the right; no injury to rectus abdominus origin and thus no “superior cleft sign”7 noted; interval resolution of mild parasymphyseal bone marrow edema; and a small nondisplaced anterosuperior acetabular labral tear of the right hip. A combined diagnostic/therapeutic right ultrasound-guided intra-articular hip joint injection (consisting of 1% lidocaine and triamcinolone) provided no immediate or further pain relief.FIGURE 1: Magnetic resonance imaging of the bony pelvis. Fat-suppressed proton density-weighted sagittal (left) and coronal (right) images show increased linear signal at the adductor longus tendon origin at the pubic body (arrow) also known as “secondary cleft sign,” indicating partial tear; the rectus abdominus tendon origin is intact.What is the best management for this patient? DIAGNOSIS/DISCUSSION OF MANAGEMENT AND OUTCOME He was diagnosed with a core muscle injury due to right partial adductor longus origin tear and tendinopathy. He already tried conservative approaches, so orthobiologic techniques were discussed, explaining the purpose, risks, benefits, and alternatives of each procedure. He chose to undergo ultrasound-guided PNT given financial limitations. After obtaining informed consent, he was placed supine with the right hip externally rotated and properly draped to reveal the right groin. Using a high-frequency linear ultrasound probe (15–6 MHz) for real-time image guidance, a 25-gauge 1.5-in needle was used to place 3 ml of 1% lidocaine without epinephrine as local anesthesia along the subcutaneous tissue and superficial to the tendon. Then, a 22-gauge 3.5-in spinal needle was placed in long axis to the probe and adductor longus tendinous fibers (Fig. 2). Gentle PNT was performed along the adductor longus tendon’s origin at the pubic tubercle, proximal fibers, and partial-thickness origin tear site, with 12–15 passes made with 10 ml of 0.25% bupivacaine injected during needle fenestration. He tolerated the procedure well. He received postprocedure instructions, which advised he be non–weight-bearing with crutches for 3 days, and then transition to weight-bearing as tolerated later in the same week. The patient underwent a supervised physical therapy program based on Finnoff et al.’s8 postprocedure rehabilitation protocol for patients after ultrasound-guided PNT and platelet-rich plasma injection for chronic tendinopathy. This included gentle stretching, range of motion exercises, and isometric strengthening in the first 2 wks, followed by isotonic strengthening and moderate resistance on a stationary bike at week 4. Core and hip abductor/extensor strengthening, lumbopelvic stability, and postural/balance training were emphasized throughout his physical therapy program.FIGURE 2: Ultrasound percutaneous needle tenotomy of the right adductor longus tendon. On the left image, a long-axis view of the partial thickness, adductor longus origin tear is seen. On the right image, needle fenestration is performed under ultrasound guidance with several passes made along the partial tear at its origin at the pubic tubercle and along the fibers of the adductor longus tendon with anesthetic.At 2 wks of follow-up, his pain was unchanged. At week 4, his pain decreased to 3/10, but he had episodic right groin pain with quick transitions or cutting motions. Use of the elliptical machine and a gradual walking to a light jogging program began at weeks 4 and 5, respectively. His pain continually improved with eccentric strengthening exercises started at 6 wks. At 2 mos, he tolerated cycling and running with less intermittent, painful episodes. At 3 mos, he returned to full running, biking, and hiking/backpacking without pain or functional limitation. Adductor tendinopathies are a major musculoskeletal cause of nonspecific groin pain, especially in sports with cutting maneuvers.2 The adductor longus is the most commonly injured.9 During running, the core muscles absorb and distribute the forces created through breathing and twisting motions.10 Abnormal muscle biomechanics lead to higher risk of overuse injuries.10 Athletes experience persistent pain and prolonged healing time due to poor vascular supply to the small, proximal transitional zone involving the adductor tendons, nerves, and periosteal bone.9 The kinetic chain abnormalities identified earlier may have contributed to the development of his adductor tendinopathy. Rehabilitation begins with core strengthening. Nearly two thirds of adductor-related pathologies will improve with this approach but may be variable.1,5 For those who do not, ultrasound-guided orthobiologic therapies provide good outcomes for return to play and are an effective minimally invasive approach.2–4 In a unrandomized case series of 75 elite-level rugby athletes with chronic groin pain, approximately 92% who received ultrasound-guided prolotherapy had improved Visual Analog Scale pain and Nirschl Pain Phase Scale scores with full return to play in 3 mos.4 Ultrasound-guided PNT for chronic tendinopathy has been safe and effective in reducing pain without complications.8 A successful ultrasound-guided PNT and platelet-rich plasma injection of the distal rectus abdominis muscle of a 20-yr-old male division I collegiate lacrosse player with chronic groin pain allowed for complete return to play 8 wks after the procedure.3 Needling is believed to break up abnormal tissue and cause localized bleeding, thus activating clot formation and growth factor release. This overall approach transforms a nonhealing chronic injury into an acute one with enhanced healing capability.8 Here, ultrasound-guided PNT possibly made a difference given that his postprocedure physical therapy program was similar to his previous rehabilitation programs. This is the first case reported on an adductor tendon origin tear treated with ultrasound-guided PNT (without platelet-rich plasma) in a long-distance runner with pain relief and return to running. This case suggests that although core muscle injuries are common in cutting sports, it may also occur in long-distance runners, specifically affecting the adductor longus tendon complex. Furthermore, ultrasound-guided PNT can be a safe and effective treatment option in refractory cases. This should be combined with a focused rehabilitation program on correcting biomechanical abnormalities to prevent further injuries. This study conforms to all American Journal of Physical Medicine and Rehabilitation Resident and Fellow Section Case Reports guidelines and reports the required information accordingly (see Supplemental Checklist, Supplemental Digital Content 1, https://links.lww.com/PHM/B340).