Existing Evidence on Ultrasound-Guided Injections in Sports Medicine

Glenohumeral Joint

The glenohumeral joint is frequently injected with corticosteroids for osteoarthritis and adhesive capsulitis. Injections into the glenohumeral joint have been studied for both accuracy and efficacy. Patel et al ²⁹ compared the accuracy of landmark-guided versus ultrasound-guided glenohumeral injections by injecting 80 cadaveric shoulders. Results of the study favored ultrasound-guided over landmark-guided injections, with accuracy being 92.5% for ultrasound-guided injections compared with 72.5% for landmark-guided injections. Lee et al ²⁴ evaluated the clinical effect of ultrasound-guided intra-articular injections compared with a landmark-guided technique for the treatment of adhesive capsulitis. The visual analog scale for pain intensity, range of motion of the shoulder, and general shoulder function during daily activities were measured at preinjection as a baseline and then every week after injection for 6 weeks for each patient. The improvements in pain intensity, range of motion, and shoulder function score were significantly greater in the ultrasound-guided injection group than in the landmark-guided injection group by the second week after injection (P < .05). However, no further significant differences were found in improvement between the 2 groups beyond the third week. Results from these studies demonstrate that ultrasound-guided injections are more accurate and efficacious than landmark-guided injections.

Acromioclavicular Joint

The acromioclavicular (AC) joint is a saddle joint at the articulation of the clavicle and acromion process. The AC is commonly affected by osteoarthritis and can be a source of pain. Corticosteroid injection into the AC joint is a common treatment. Until recently, the AC joint was thought easy to palpate and inject using landmark guidance. However, Rho et al ³⁶ found that accuracy of landmark-guided palpation of the AC joint was only 16.7% among physiatry residents.

Peck et al ³¹ performed a study in which 20 unembalmed cadaveric AC joints were injected. All ultrasound-guided injections were successfully placed into the AC joint (10/10, 100%), whereas only 4 of 10 (40%) landmark-guided AC joint injections were accurate (P = .0054). Sabeti-Aschraf et al ³⁷ conducted a prospective, randomized, observer-blinded study in which 120 AC joints of 60 cadavers were injected by use of an ultrasound-guided method or a landmark-guided method. The landmark-guided injection was inaccurate 25% of the time compared with 3% inaccuracy when ultrasound guidance was used (P = .009). Borbas et al ⁷ also evaluated the accuracy of ultrasound-guided injection versus landmark-guided injection of the AC joint. Those investigators showed 90% accuracy for ultrasound-guided injections compared with 70% accuracy for landmark-guided injections (P = .025). A review by Aly et al ² in 2015 showed that the accuracy of ultrasound-guided versus landmark-guided injections was 93.6% versus 68.2%, respectively (P < .0001).

Another study analyzed 20 patients who were assigned to either an ultrasound-guided or a landmark-guided group. Clinical examinations were performed before treatment and at 1 hour, 1 week, and 3 weeks after an injection into the AC joint. ³⁸ Both groups had improvement in pain and function; however, no significant difference was found between the two groups. To date, although ultrasound-guided injections are clearly more accurate than landmark-guided injections, it is yet to be determined whether ultrasound-guided injections to the AC joint are more efficacious than landmark-guided injections.

Subacromial Space

Mixed evidence is available on the benefits of ultrasound-guided subacromial injections. Several studies have revealed no significant difference in accuracy between ultrasound-guided and landmark-guided injections of the subacromial space. ^8,17,19 Some limited evidence is available for increased pain relief after ultrasound-guided subacromial-subdeltoid bursal injections. ¹⁷

Ucuncu et al ⁴⁶ evaluated 60 patients with shoulder pain due to soft tissue disorders who were randomly assigned to receive triamcinolone 40 mg by either landmark-guided or ultrasound-guided injection. The patients were evaluated on admission and at 6 weeks after the injection. Clinical assessment included a visual analog scale for pain, the Constant scale for function, passive and active shoulder range of motion, and postinjection adverse effects. Those patients receiving an ultrasound-guided injection showed statistically significant improvements in visual analog scale for pain and Constant scores for function at 6 weeks after injection when compared with the landmark-guided group. Improvement in active and passive range of motion was observed in both groups, with the ultrasound-guided group showing superior improvement. Of the patients with limited shoulder range of motion, 50% who underwent ultrasound-guided injections returned to normal motion, while only 33% of those who underwent landmark-guided injection returned to normal (P < .05). Range of motion in abduction of the shoulder in the landmark-guided injection group improved from 71.03° ± 12.38° prior to injection to 100° ± 18.18° at 1 week after the injection. The range of motion in the ultrasound-guided injection group improved to 139.29° ± 20.14° after 1 week, from initial range of motion of 69.05° ± 14.72° (P < .05).

The currently available evidence indicates that ultrasound-guided subacromial injections may be superior to landmark-guided injections. Most of the studies completed to this point used small sample sizes and did not evaluate cost-effectiveness. Larger studies are needed to determine the true efficacy of ultrasound-guided injection into the subacromial space.

Long Head of the Biceps Tendon

Zhang et al ⁵⁴ conducted a randomized prospective study of 98 patients with tendinopathy of the long head of the biceps tendon. The patients were randomized to receive either an ultrasound-guided injection or landmark-guided injection into the bicep tendon sheath. In the ultrasound-guided group, the visual analog scale score significantly decreased (P < .05) and the Constant-Murley score improved (P < .01).

Hashiuchi et al ²⁰ studied 30 patients with reported anterior shoulder pain with a primary diagnosis of tenosynovitis, tendinitis of the biceps tendon, or both. Shoulders were randomly allocated into ultrasound-guided and landmark-guided injection groups. Computed tomography (CT) imaging was performed immediately after a contrast agent was injected into the biceps tendon sheath. Ultrasound guidance resulted in 86.7% of injections into the tendon sheath, whereas landmark guidance resulted in 26.7% into the tendon sheath, which was a significant difference (P < .05).

The results demonstrate that ultrasound-guided injections of the bicep tendon sheath are more accurate and efficacious than landmark-guided injections.

Elbow Joint

Few studies have evaluated ultrasound-guided injection of the elbow joint. Lopes et al ²⁶ conducted a prospective study to evaluate the accuracy of intra-articular injections in peripheral joints. Within this study, 31 elbows were injected by use of landmark guidance only, and 100% were successfully injected. Cunnington et al ⁹ conducted a double-blinded, randomized controlled study of ultrasound-guided corticosteroid joint injections in patients with inflammatory arthritis. Twenty-two elbows were injected, and ultrasound guidance was accurate 91% of time compared with landmark guidance at 64%; however, this was not statistically significant (P = .100). Data on efficacy of ultrasound-guided injections of the elbow joint are quite limited at this time.

Hand and Wrist Joints

Multiple small studies have evaluated accuracy of aspiration and injection of various joints in the wrist and hand. Smith et al ⁴² performed a randomized controlled trial comparing the accuracy of ultrasound-guided versus landmark-guided injection at the scaphotrapeziotrapezoid joint in cadaveric models. Accuracy of ultrasound-guided injections was 100%, whereas accuracy of landmark-guided injections was 80%. Another study evaluated ultrasound-guided distal radioulnar joint injections, reporting 100% accuracy. ⁴⁵ Umphrey et al ⁴⁷ performed ultrasound-guided injections of the trapeziometacarpal joint and reported that 94% of injections were successful. Pollard et al ³² investigated the accuracy of intra-articular injection of the basal joint; the success rate was 100% for the ultrasound-guided group compared with 81.8% for the landmark-guided group. Goncalves et al ¹⁸ conducted a case series demonstrating that ultrasound-guided injections of the metacarpophalangeal joint were efficacious and visual analog scale scores were improved. Raza et al ³⁴ assessed the accuracy of proximal interphalangeal (PIP) and metacarpophalangeal (MCP) joint injections: Palpation-guided injections were intra-articular 59% of the time (6/12 PIP and 4/5 MCP joints) compared with 96% (24/26 PIP and 27/27 MCP joints) for ultrasound guidance.

Hip Joint

Only 2 studies have assessed the accuracy of landmark-guided hip joint injections. Ziv et al ⁵⁵ and Diracoglu et al ¹² separately studied landmark-guided hip joint injections in a total of 56 patients and showed an accuracy of 77.5% and 66.7%, respectively. Studies of ultrasound-guided injections have reported 100% accuracy ^25,27 with the exception of Smith et al, ⁴⁴ who reported 97% accuracy in a group of 28 patients. In this study, the one injection that was not intra-articular was due to a single episode of inadvertent needle withdrawal during attachment of extension tubing for contrast administration. ⁴⁴ The efficacy of ultrasound-guided injection has been evaluated in patients with hip pain related to osteoarthritis. A case series (N = 10) by Pourbagher et al ³³ in 2005 found that 80% of patients had improved function and less pain at 6 months postinjection. Micu et al ²⁷ compared ultrasound-guided injections versus no injection in a group of 61 patients; at 1- and 3-month follow-ups, the authors noted reduction in pain in those patients receiving injections but no change in pain in the group that did not receive injections. Yoong et al ⁵³ evaluated the utility of ultrasound-guided hip joint injection in predicting surgical outcomes. In that study, 138 patients underwent ultrasound-guided injection with local anesthetic to aid in diagnosis of hip disease prior to surgical hip arthroscopy. Yoong et al ⁵³ found that 93% of patients who had pain relief after injection had successful surgical outcomes, compared with 63% of patients with partial relief; 44 of 49 patients who had no relief from the injection ultimately did not have hip surgery.

A retrospective study by Migliore et al ²⁸ in 2011 involving 2343 patients showed that ultrasound-guided intra-articular hip joint injection with hyaluronic acid for hip osteoarthritis decreased consumption of nonsteroidal anti-inflammatory drugs (NSAIDs). Consumption was decreased 48.2% at the 3-month follow-up, followed by a 50% decrease at the 12-month follow-up and a 61% decrease at the 24-month follow-up. This could lead to significantly decreased long-term health care costs as a result of a reduction in NSAID-induced complications.

Iliopsoas Bursa Injection

Anterior hip pain is commonly encountered by the orthopaedic and sports medicine provider. Snapping hip is a cause of anterior hip pain and affects 5% to 10% of the general population. Snapping hip syndrome can be caused by tightness and inflammation of the iliopsoas tendon leading to an audible or palpable snap as the hip moves from flexion to extension. When painful, this condition can respond to injection.

Few studies have been completed assessing pain relief of snapping hip with image-guided injections. In 2005, Adler et al ¹ completed a retrospective review of ultrasound-guided injections into the iliopsoas bursa. The investigators enrolled 39 patients and injected an 8-mL solution of anesthetic and corticosteroid into the iliopsoas bursa. They conducted telephone follow-up to assess pain, with a mean follow-up period of 13.5 months. The investigators showed that 44% of the patients had continued relief of symptoms at 1 year after the injection. No major complications were reported.

In 2006, Blankebaker et al ⁵ conducted a retrospective study to assess pain relief achieved from anesthetic injection of the iliopsoas bursa and also assessed the effectiveness of Kenalog injection into the iliopsoas bursa for long-term pain relief. For this study, long-term pain relief was interpreted as improvement of pain for 4 months following injection. Forty patients were enrolled: 22 received ultrasound-guided injection of the iliopsoas bursa with a 7-mL mixture containing lidocaine and bupivacaine, while 18 received ultrasound-guided injection with an 8-mL mixture containing lidocaine, bupivacaine, and Kenalog-40. Injection response was monitored using an 11-point pain scale that was assessed 2 days after the procedure. Those patients undergoing injection with Kenalog were observed for an additional 4 months after injection. Twenty-nine patients had complete or partial relief of pain (>50% pain reduction) from iliopsoas bursal injection 2 days after the injection. Sixteen of the 18 patients (89%) who underwent Kenalog injection had improvement of pain after 4 months.

In 1989, Silver et al ⁴¹ reported a single case where the patient had complete relief of symptoms related to snapping hip 2 months after image-guided injection with solution of anesthetic and corticosteroid (Depo-Medrol). In a case series of 3 athletes published in 2004, Wahl et al ⁴⁹ showed that ultrasound-guided injection with anesthetic and corticosteroid provided short-term relief for all patients up to 2 weeks after the injection. Two of the 3 patients experienced long-term relief of symptoms for more than 2 years. In 1995, Vaccaro et al ⁴⁸ showed a similar response in 8 patients undergoing ultrasound-guided injection of anesthetic and corticosteroid into the iliopsoas bursa. Those 8 patients had relief of symptoms for periods ranging from 2 weeks to 2 years.

The above studies show that ultrasound-guided injection into the iliopsoas bursa is well tolerated and does not have significant adverse complications. ^48,49 Landmark-guided injections are generally not performed at this location because of the proximity to the femoral vascular structures. ⁵ A low risk of infection and vascular injuries is found with ultrasound-guided iliopsoas bursa injection.

Knee

Osteoarthritis is a common condition affecting the knee and is often treated with corticosteroid injections. Accuracy of landmark-guided injections is somewhat variable but generally good. Studies from 1993 onward demonstrate a wide margin of accuracy with respect to landmark-guided injection, ranging from 55% to 100%, which is often dependent on the approach taken. A case series by Lopes et al ²⁶ in 2008, comprising 37 patients, appears to be the only landmark-guided injection study to report 100% accuracy as well as efficacy. In 2002, Jackson et al ²² showed 93% accuracy for lateral midpatellar, 75% for anteromedial, and 71% for anterolateral landmark-guided approaches.

In 2007, Esenyel et al ¹⁵ showed 85% accuracy for an anterolateral approach and 56% for medial midpatellar tendon, with 73% and 76% for anteromedial and lateral midpatellar, respectively. Systematic reviews of landmark-guided injections of the knee conducted by Daley et al ¹¹ and Hermans et al, ²¹ both published in 2011, reported accuracy rates from 67% to 91% based on approach, with a superolateral approach being most accurate (91%). Daley et al ¹¹ did not find statistically significant differences in approach.

Curtiss et al, ¹⁰ in a cadaveric ultrasound-guided versus landmark-guided study published in 2011, showed a range of accuracy of 55% to 100% in the landmark-guided group. The results for landmark-guided injections were dependent upon the injector, while the ultrasound-guided injections were 100% accurate regardless of injector.

In other head-to-head studies, ultrasound-guided injections were universally found to be more accurate than landmark-guided injection. In a 2012 review, Berkoff et al ⁴ examined 13 relevant studies, with ultrasonography used in 5 studies and the remaining studies using air arthrography, fluoroscopy, magnetic resonance arthrography, or magnetic resonance imaging. The accuracy of injection ranged from 63% to 100% with ultrasonography, while the accuracy ranged from 39% to 100% with landmark guidance. Accuracy was 95.8% with ultrasound guidance versus 77.8% without ultrasound guidance.

Sibbitt et al ^39,40 examined both efficacy and cost-effectiveness of knee injections in patients with inflammatory arthropathy. First, in 2011, in a prospective, randomized controlled trial of 94 patients, the investigators showed greater accuracy with ultrasound-guided injection. ³⁹ This study also concluded that ultrasound guidance improves clinical outcomes by increasing therapeutic duration. The increased therapeutic duration leads to less utilization of health care resources and overall reduction in yearly health care costs. Similar findings were achieved in the 2012 study by Sibbitt et al ⁴⁰ of 64 patients. These studies were performed in patients with inflammatory arthropathy, and one should be cautious extrapolating these data to noninflammatory arthropathies.

Foot and Ankle

Several studies have examined the accuracy of landmark-guided and ultrasound-guided foot and ankle joint injections. Accuracy in these studies ranged from 58% to 85% for landmark-guided injections, while ultrasound-guided injections were universally 100% accurate in each study. ^{18,23,35,43,50,51} Of note, Khosla et al ²³ showed 100% accuracy in a head-to-head cadaveric study of both ultrasound-guided and landmark-guided injections (N = 14) for the tibiotalar joint and subtalar joints, suggesting that either modality would be sufficient. With tarsometatarsal joint injections, ultrasound-guided injections were vastly more accurate than landmark-guided injections, at 64% versus 24%, respectively. Reach et al ³⁵ (N = 10) and Wempe et al ⁵⁰ (N = 5) in 2009 and 2012, respectively, both showed 100% accuracy in cadaveric ultrasound-guided injection of the metatarsophalangeal joints. Goncalves et al ¹⁸ found excellent efficacy in both tibiotalar joint and tarsometatarsal joint injections, with 100% of patients showing clinical improvement following the procedure. In addition, Drakonaki et al ¹³ showed that a majority of patients with midfoot degenerative disease experienced relief up to 3 months following ultrasound-guided injection.