Comparison of four different intra-articular injection sites in the knee: a cadaver study

The preferred technique for knee synovium biopsy and synovial fluid arthrocentesis

For knee osteoarthritis and related conditions, analysis of biomarkers hold promise to improve early diagnosis and/or offer patient-specific treatment. To compare biomarker analyses, reliable, high-quality biopsies are needed. The aim of this work is to summarize the literature on the current best practices of biopsy of the synovium and synovial fluid arthrocentesis. Therefore, PubMed, Embase and Web of Science were systematically searched for articles that applied, demonstrated, or evaluated synovial biopsies or arthrocentesis. Expert recommendations and applications were summarized, and evidence for superiority of techniques was evaluated. Thirty-one studies were identified for inclusion. For arthrocentesis, the superolateral approach in a supine position, with a 0°-30° knee flexion was generally recommended. 18-gage needles, mechanical compression and ultrasound-guidance were found to give superior results. For blind and image-guided synovial biopsy techniques, superolateral and infrapatellar approaches were recommended. Single-handed tools were preconized, including Parker-Pearson needles and forceps. Sample quantity ranged approximately from 2 to 20. Suggestions were compiled for arthrocentesis regarding approach portal and patient position. Further evidence regarding needle size, ultrasound-guidance and mechanical compression were found. More comparative studies are needed before evidence-based protocols can be developed.

Clinical and Functional Outcome of Meniscal Injuries Treated with Platelet-Rich Plasma: A Single-Center Case Series

Meniscal injuries are among the most frequently encountered conditions in the knee joint. Therapeutic approaches are diverse and are largely dependent on the extent and location of the injury. The purpose of this study was to describe the clinical and functional outcomes of an intraarticular and percutaneous platelet-rich plasma (PRP) injection regime in patients with stable meniscal injuries. Demographics, the type of tear, affected knee, surgical procedure, type of intervention, follow-up period, and outcomes were recorded in all cases. Patient-reported outcome measures included the Knee Injury and Osteoarthritis Outcome Score (KOOS) and Tegner activity level scale. Overall patient satisfaction, quality of life, and pain intensity were also assessed. A total of 38 cases (8 females) had sustained a stable meniscal lesion (32 medial, 6 lateral) and met the inclusion criteria. All of them received three intraarticular and percutaneous PRP injections. Patients receiving the PRP injection regime reported clinically (p = 0.000) and functionally (p = 0.000 and p = 0.001) significant improvement in all outcome measures during this interval. All patients reported they were very satisfied or satisfied with the outcome. The results of this study suggest that the treatment of stable meniscal injuries with percutaneous-intraarticular PRP injections can achieve a significant clinical and functional improvement.

Ultrasound-Guided Knee Injections Are More Accurate Than Blind Injections: A Systematic Review of Randomized Controlled Trials

Purpose

To review the current literature to determine which injection technique and needle portal placement provide the greatest accuracy for intra-articular access to the knee.

Methods

This study followed Preferred Reporting Items and Systematic Reviews and Meta-Analyses guidelines. A comprehensive literature search was conducted in March 2020 and repeated in May 2020 using electronic databases PubMed, MEDLINE, and the Cochrane Library. Data on the accuracy of intra-articular knee injection (successful injections/total number of injections) were collected. Only Level I studies were included. Study design, demographic variables, needle sizes, and method of validating accuracy were recorded. The Jadad score was used to assess methodologic quality, and a risk-of-bias assessment was performed.

Results

A total of 12 Level I human studies (1431 patients, 1315 knees) were included in this review. Seven of the studies did a direct comparison between ultrasound-guided and blind knee injections. Ultrasound-guided injections were more accurate compared with blinded knee injections in every study. The most accurate anatomical approach was an isometric quadricep contraction method with the superolateral approach.

Conclusions

This study showed that ultrasound-guided knee injections were more accurate across every anatomical needle injection site compared with blind injections. Injections made by a blind/anatomically guided method had inconsistent accuracy rates that seemed highly dependent on the portal of entry.

Level of Evidence

Level I, systematic review of Level I studies.

The Impact of an Ultrasound Curriculum on the Accuracy of Resident Joint Line Palpation

BACKGROUND

Ultrasound education has been used as a tool to help improve physical examination skills. However, its utility in increasing accuracy of joint line palpation has yet to be investigated.

OBJECTIVE

To evaluate the accuracy of resident palpation and identification of the lateral knee joint line before and after introducing a musculoskeletal ultrasound (MSUS) curriculum.

DESIGN

Cohort study.

SETTING

A physical medicine and rehabilitation (PM&R) residency program at an academic institution.

PARTICIPANTS

Seventeen PM&R residents.

INTERVENTIONS

Residents underwent a knee-focused MSUS workshop.

MAIN OUTCOME MEASURES

Distance from needle placement to joint line confirmed with ultrasound.

RESULTS

All residents demonstrated improved accuracy in lateral knee joint line palpation after completing a knee-focused MSUS workshop, with statistically significant (P < .05) improvement in postgraduate year (PGY) 2 (P = .02), PGY-3 (P = .04), and across all residents (P = .001).

CONCLUSIONS

MSUS education significantly improved lateral knee joint line palpation accuracy in resident physicians.

Injection route affects intra-articular hyaluronic acid distribution and clinical outcome in viscosupplementation treatment for knee osteoarthritis: a combined cadaver study and randomized clinical trial

The coverage of hyaluronic acid (HA) on the impaired cartilage should be the precondition to exert its beneficial effect on knee osteoarthritis (KOA) according to the pharmacological mechanism. However, the intra-articular distribution of HA might be correlated with the route of drug delivery. Forty-two cadaver knees with radiographic evidence of osteoarthritis were given anteromedial (AM) or medial midpatellar (MMP) injection of HA (molecular weight 600-1500 kD) followed by gait stimulation. Although 2.5 ml HA delivered through both routes failed to cover the entire cartilage, HA covered 96.12% cartilage of patellofemoral joint (PFJ) and 71.44% of medial femorotibial joint (FTJ) through MMP route, whereas mainly distributed into FTJ and posterior condyles through AM route. HA in the MMP group distributed more in PFJ than that in the AM group (P < 0.001), but no significant difference presented in medial FTJ (P = 0.084). The clinical efficacy was also associated with the route of drug delivery. One hundred patients with unilateral mild-to-moderate KOA were recruited and randomly assigned to receive five weekly HA injections with AM route (n = 50) or MMP route (n = 50). Patients in the MMP group obtained better improvement in WOMAC index total score, pain score, stiffness score, and Lequesne index total score over the entire follow-up period, as compared to patients in the AM group (all P < 0.01). More patients in the MMP group claimed pain relief (71.7%, P = 0.024) and felt satisfying (63.1%, P = 0.007) than in the AM group at the end of follow-up. Therefore, intra-articular HA injection through MMP route is recommended in treating mild-to-moderate KOA. Graphical Abstract .

BRAZILIAN CONSENSUS STATEMENT ON VISCOSUPPLEMENTATION OF THE KNEE (COBRAVI)

Objective:

The aim of this consensus statement on viscosupplementation is to serve as a reference document based on relevant literature and clinical experience in the treatment of knee osteoarthritis using an intra-articular injection of hyaluronic acid, covering key aspects such as clinical indications, effectiveness, and tolerability.

Methods:

A multidisciplinary panel including two sports medicine physicians, six orthopedists, four physiatrists, and two rheumatologists were selected based on their clinical and academic experience of viscosupplementation. Sixteen statements were prepared and discussed, after which a vote was held. Each member of the panel gave a score between 0 and 10 on a Likert scale, specifying their level of agreement with the statement.

Results:

The panel reached a consensus on several issues. Specifically, the panel agreed that the best indication is for mild to moderate knee arthrosis; prior or concomitant use of intraarticular triamcinolone hexacetonide may optimize the effect of hyaluronic acid; viscosupplementation should not be performed as an isolated procedure but in conjunction with other rehabilitative and pharmacological measures; viscosupplementation has analgesic, anti-inflammatory, and chondroprotective effects; and viscosupplementation is cost-effective.

Conclusion:

This consensus statement provides clear information and guidance for both individuals and payers. Level of evidence V, Consensus statement.

Echo-guided invasive pain therapy: indications and limitations

PURPOSE OF REVIEW

The purposes of this review are to summarize the advantages and limitations of ultrasound-guided pain interventions, and to illustrate those interventions with peripheral, axial and musculoskeletal pain procedures.

RECENT FINDINGS

With the capability of locating the interfascial plane, ultrasonography has led to the emergence of a series of plane blocks for the thoracoabdominal region in the recent decade.Ultrasonography for musculoskeletal procedures has been of growing interest because of the major advantage of direct visualization and scanning of various soft tissues and real-time spread in the injectate, thereby enhancing precision and efficacy, reducing risk of trauma and avoidance of radiation. For spine and intra-articular structures, ultrasonography is complicated by the bony shadow artefact and often deep location of the structure, making acquisition of ultrasound image challenging. Despite these difficulties, there is growing interest in applying ultrasonography for cervical spine and sacroiliac joint procedures.

SUMMARY

Pain intervention under ultrasound guidance is particularly valuable in peripheral and musculoskeletal procedures. There is growing interest of its application in cervical spine and sacroiliac joint. More outcome studies are required in the future to make ultrasound-guided pain intervention as the established procedure.

Isometric Contraction of the Quadriceps Improves the Accuracy of Intra-Articular Injections into the Knee Joint via the Superolateral Approach

Background:

Intra-articular injection is an important technique for treating rheumatoid arthritis and osteoarthritis of the knee. However, medication is often inaccurately injected outside of the joint. We devised an intra-articular injection method in which the needle is inserted into the suprapatellar bursa while the patient maintains isometric contraction of the quadriceps. This isometric contraction method is based on the concept that isometric contraction of the quadriceps induces contraction of the articularis genus muscle, thus expanding the lumen of the suprapatellar bursa.

Methods:

Intra-articular injections were performed on 150 osteoarthritic knees without effusion. The knees were alternately assigned to the isometric quadriceps method group (75 knees) and non-activated quadriceps method group (75 knees). Prior to joint injection, the anterior-posterior dimension of each suprapatellar bursa was measured to ascertain its expansion. The isometric quadriceps method was performed with the quadriceps and the articularis genus muscle maintained in a contracted state. The non-activated quadriceps method was performed in a relaxed state. Ultrasound guidance was not used for either method. Subsequently, an ultrasonic probe was used only to confirm whether the intra-articular injections were successful. We compared the accuracy of injections performed between the 2 groups.

Results:

Suprapatellar expansion was significantly larger (p < 0.001) using the isometric quadriceps method (2.1 ± 1.4 mm [range, 0 to 5 mm]) than using the non-activated quadriceps method (0.8 ± 0.7 mm [range, 0 to 2 mm]). The percentage of accurate intra-articular injections was significantly higher (p = 0.0287) using the isometric quadriceps method (93%) compared with the non-activated quadriceps method (80%).

Conclusions:

In comparison with the non-activated quadriceps method, the isometric quadriceps method led to a larger expansion of the suprapatellar bursa, which should lead to more accurate intra-articular injections. The isometric quadriceps method is effective in reducing inaccurate injections into the synovium or surrounding fatty tissues.

Clinical Relevance:

Putting force on the quadriceps muscle increases the success rate of intra-articular injection of the knee. The results of this study could provide a clinically relevant injection technique for future treatment.

The comparison of two different intraarticular injections using a sonographic anterolateral approach in patients with osteoarthritic knee

Background

The intraarticular (IA) injection has become popular for the management of the osteoarthritic knee without an effusion. The success rate of IA injection would be better if it was able to be visually confirmed. We hypothesized that an anterolateral approach, which targets the synovial membrane of the lateral condyle using ultrasound, would provide an equivalent alternative to the anterolateral approach, targeting the synovial membrane of the medial condyle for IA injection of the knee.

Methods

A total of 96 knees with osteoarthritis were randomized placed into the two groups, which were group I (anterolateral approach to the medial condyle) and group II (anterolateral approach to the lateral condyle). The primary outcome was to compare the success rate of the two methods of IA injection. The required length of the needle for injection was also measured and compared. Pain intensity was assessed using the Numeric Rating Scale in order to evaluate the success of injection.

Results

There were no significant differences in the success rate between both groups. The success rate of group I and group II were 87.8% (95%, CI 78.7–97.0) and 91.5% (95%, CI 83.6–99.5), respectively (P = 0.549). The needle depth was 5.0 ± 0.8 (3.0 to 6.1 cm) in group I, and 3.0 ± 0.8 (1.5 to 5 cm) in group II (P < 0.001).

Conclusions

The anterolateral approach to the lateral femoral condyle, using ultrasound, is an alternative method to the approach targeting the medial femoral condyle, using shorter needle.

Existing Evidence on Ultrasound-Guided Injections in Sports Medicine

Office-based ultrasonography has become increasingly available in many settings, and its use to guide joint and soft tissue injections has increased. Numerous studies have been conducted to evaluate the use of ultrasound-guided injections over traditional landmark-guided injections, with a rapid growth in the literature over the past few years. A comprehensive review of the literature was conducted to demonstrate increased accuracy of ultrasound-guided injections regardless of anatomic location. In the upper extremity, ultrasound-guided injections have been shown to provide superior benefit to landmark-guided injections at the glenohumeral joint, the subacromial space, the biceps tendon sheath, and the joints of the hand and wrist. Ultrasound-guided injections of the acromioclavicular and the elbow joints have not been shown to be more efficacious. In the lower extremity, ultrasound-guided injections at the knee, ankle, and foot have superior efficacy to landmark-guided injections. Conclusive evidence is not available regarding improved efficacy of ultrasound-guided injections of the hip, although landmark-guided injection is performed less commonly at the hip joint. Ultrasound-guided injections are overall more accurate than landmark-guided injections. While current studies indicate that ultrasound guidance improves efficacy and cost-effectiveness of many injections, these studies are limited and more research is needed.

Comparison of the 3 Different Injection Techniques Used in a Randomized Controlled Study Evaluating a Cross-Linked Sodium Hyaluronate Combined With Triamcinolone Hexacetonide (Cingal) for Osteoarthritis of the Knee: A Subgroup Analysis

A recent trial demonstrated that patients with knee osteoarthritis treated with a sodium hyaluronate and corticosteroid combination (Cingal) experienced greater pain reductions compared with those treated with sodium hyaluronate alone (Monovisc) or saline up to 3 weeks postinjection. In this study, injections were administered by 1 of 3 approaches; however, there is currently no consensus on which, if any, of these techniques produce a more favorable outcome. To provide additional insight on this topic, the results of the previous trial were reanalyzed to determine whether (1) the effect of Cingal was significant within each injection technique and (2) pain reductions were similar between injection techniques across all treatment groups. Greater pain reductions with Cingal up to 3 weeks were only significant in the anteromedial subgroup. Across all therapies, both the anteromedial and anterolateral techniques demonstrated significantly greater pain reductions than the lateral midpatellar approach at 18 and 26 weeks.

In-Plane Ultrasound-Guided Knee Injection Through a Lateral Suprapatellar Approach: A Safe Technique

PURPOSE

This study aims to describe a technique for in-plane ultrasound-guided knee arthrography through a lateral suprapatellar approach, reporting its accuracy and related complications.

METHODS

A retrospective search was performed for computed tomography and magnetic resonance reports from June 2013 through June 2015. Imaging studies, puncture descriptions, and guided-procedure images were reviewed along with clinical and surgical history. A fellowship-trained musculoskeletal radiologist performed all procedures under sterile technique and ultrasound guidance with the probe in oblique position on the lateral suprapatellar recess after local anesthesia with the patient on dorsal decubitus, hip in neutral rotation, and 30 to 45 degrees of knee flexion.

RESULTS

A total of 86 consecutive subjects were evaluated (mean, 55 years). All subjects underwent intra-articular injection of contrast, which was successfully reached in the first attempt in 94.2% of the procedures (81/86), and in the second attempt in 5.8% (5/86) after needle repositioning without a second puncture. There were no postprocedural reports of regional complications at the puncture site, such as significant pain, bleeding, or vascular lesions.

CONCLUSIONS

Our study demonstrates that in-plane ultrasound-guided injection of the knee in semiflexion approaching the lateral suprapatellar recess is a safe and useful technique to administer intra-articular contrast solution, as an alternative method without radiation exposure.

Musculoskeletal interventional procedures: With or without imaging guidance?

Aspiration and injection of joints and soft tissues is an indispensable skill used in everyday practice by the clinical rheumatologist. Most rheumatologists recognise that performing these procedures using anatomical landmarks is not always successful, particularly in the case of small or infrequently injected joints, bursae or tendon sheaths. Musculoskeletal ultrasound confirms the local pathological-anatomical diagnosis and is the most applicable and feasible imaging method that can be applied in clinical practice in guiding musculoskeletal interventional procedures. From 1993, there has been substantial examination of the accuracy of landmark- and imaging-guided procedures. We have searched the literature and ascertained whether imaging techniques improve the accuracy of musculoskeletal procedures and whether the accuracy of needle placement can be translated into improved clinical outcome (efficacy).

Inferomedial or Inferolateral Intra-articular Injections of the Knee to Minimize Pain Intensity

Pain levels of 3 knee intra-articular corticosteroid injection sites were assessed to determine if an optimal site exists. Patients were stratified by site, demographic, and disease characteristics. All injections were performed by 1 surgeon using a uniform technique. Pain severity was assessed before, 1 minute after, and 5 minutes after injection using a visual analog scale. Mean visual analog scale scores for the lateral suprapatellar, medial infrapatellar, and lateral infrapatellar injection sites were 7, 4, and 2 points, respectively, but this was not statistically significant. These results suggest intra-articular injections should be administered from an inferomedial or inferolateral site to minimize pain intensity. [Orthopedics. 2016; 39(3):e578-e581.].

Effectiveness of Ultrasound Guidance on Intraarticular and Periarticular Joint Injections: Systematic Review and Meta-analysis of Randomized Trials

OBJECTIVE

The aim of this study was to evaluate the effectiveness and accuracy of ultrasound-guided intraarticular and periarticular joint injections as compared with landmark-guided injections technique.

METHODS

A systematic literature search was performed in Medline, Web of Science, Embase, the Cochrane Central Register of Controlled Trials, reference lists of articles, and other sources. Only randomized controlled trials were included. Two reviewers independently selected and assessed each study for quality and extracted data.

RESULTS

Twelve randomized controlled trials were included in the meta-analysis. The results indicated that ultrasound-guided intraarticular and periarticular joint injections were more accurate than the landmark-guided injections (odds ratio, 0.36; 95% confidence interval, 0.22-0.60). Ultrasound-guided joint injections significantly decreased the visual analog scale scores at both 2 wks (mean difference, -9.57; 95% confidence interval, -13.14 to -5.99) (P < 0.00001) and 6 wks (mean difference, -14.21; 95% confidence interval, -18.20 to -10.21) (P < 0.00001) after injection. There was no statistically significant difference in visual analog scale score at 12 wks between ultrasound-guided and landmark-guided intraarticular and periarticular joint injections (mean difference, -4.42; 95% confidence interval, -11.71 to 2.87) (P = 0.23).

CONCLUSIONS

Intraarticular and periarticular injections using ultrasound guidance significantly improves the accuracy of joint injections, and there is a significant decrease in visual analog scale scores for up to 6 wks after injection. The effect of ultrasound guidance on the long-term outcome of joint injections is inconclusive. The improved accuracy of injections was associated with pain relief. The authors recommend routine ultrasound guidance for intraarticular and periarticular injections.

Ultrasound-guided versus landmark in knee arthrocentesis: A systematic review

OBJECTIVES

The objective was to assess the efficacy of ultrasound-guided (USG) versus landmark (LM) knee arthrocentesis in adults with knee pain or effusion.

METHODS

A systematic review of the literature was performed until August 2015. All controlled trials reporting the accuracy or clinical efficacy between USG and LM knee joint arthrocentesis were selected. Pooled weighted mean difference (WMD) using the D-L fixed models for continuous outcomes and the risk ratio (RR) for dichotomous outcomes were assessed by meta-analysis. Heterogeneity between studies was estimated by I(2) statistic.

RESULTS

Nine studies including 715 adult patients (725 knee joints) were eligible for this review versus LM group; there was a statistically significant difference in favor of USG for knee arthrocentesis accuracy rate (risk ratio = 1.21; 95% CI: 1.13-1.29; P < 0.001; I(2) = 37%), lower procedural pain scores (WMD = -2.24; 95% CI: -2.92 to -1.56; P < 0.001; I(2) = 4%), more aspiration volume (WMD = 17.06; 95% CI: 5.98-28.13; P = 0.003; I(2) = 57%), and decreased pain score 2 weeks after injection (WMD = 0.84; 95% CI: 0.42-1.27; P < 0.001; I(2) = 0). There was no statistically significant difference in procedural duration between two groups (WMD = -0.8; 95% CI: -2.24 to 0.74; P = 0.31; I(2) = 0).

CONCLUSIONS

Ultrasound-guided knee joint arthrocentesis offer a significantly greater accuracy and clinical improvement over landmark technique in adults with knee pain or joint effusion.

American Medical Society for Sports Medicine (AMSSM) position statement: interventional musculoskeletal ultrasound in sports medicine

The use of diagnostic and interventional ultrasound has significantly increased over the past decade. A majority of the increased utilization is by nonradiologists. In sports medicine, ultrasound is often used to guide interventions such as aspirations, diagnostic or therapeutic injections, tenotomies, releases, and hydrodissections. This American Medical Society for Sports Medicine (AMSSM) position statement critically reviews the literature and evaluates the accuracy, efficacy, and cost-effectiveness of ultrasound-guided injections in major, intermediate, and small joints, and soft tissues, all of which are commonly performed in sports medicine. New ultrasound-guided procedures and future trends are also briefly discussed. Based upon the evidence, the official AMSSM position relevant to each subject is made.

Short-term efficacy to conventional blind injection versus ultrasound-guided injection of local corticosteroids in tenosynovitis in patients with inflammatory chronic arthritis: A randomized comparative study

OBJECTIVE

To compare the short-term efficacy of conventional blind injection (CBI) versus ultrasound-guided injection (USGI) of corticosteroids (CS) injection in tenosynovitis in patients with chronic arthritis and to investigate if the USGI is a less painful procedure and if there are differences in the changes of US findings during the post injection follow-up.

METHODS

Patients presenting tenosynovitis requiring CS injection were involved. After clinical and US evaluation, patients were randomized to receive CBI or USGI. Efficacy of procedure was assessed by the improvement in both Health Assessment Questionnaire (HAQ) and pain visual analogue scale (VAS), including procedure-VAS global-VAS and local-VAS, after 1 and 4 weeks post-procedure. Power Doppler (PD) and greyscale (GS) US findings were also object of the follow-up. CBI or USGI under an aseptic technique were performed according the local guidelines using 20mg of methylprednisolone acetate.

RESULTS

A total of 114 patients were randomized to receive CBI (54 patients) or USGI (60 patients) procedure. No significant difference was observed in terms of gender, age and pain duration among CBI and USGI groups at baseline. USGI proved to be significantly less painful than CBI (P=0.0001). AUC analysis showed that during the follow up visits, the USGI procedure had significantly better response in HAQ, local-VAS and global-VAS (P=0.0001, P=0.012 and P=0.0001 respectively) compared to CBI. During the follow up period, a significant greater reduction in the PD scores was found in the USGI group compared to the CBI group (P=0.0002), whereas no statistical differences were found in the GS findings between the groups (P=0.5627).

CONCLUSION

Our study demonstrates superiority of USGI over CBI for CS injections in painful tenosynovitis, having better short-term outcomes measured by functional, clinical and US scores. These data support the use of USGI for tenosynovits in typical inpatient and/or outpatient in rheumatological practices.

Tolerability and Efficacy of 3 Approaches to Intra-articular Corticosteroid Injections of the Knee for Osteoarthritis: A Randomized Controlled Trial

BACKGROUND

Several studies have been performed suggesting that a superolateral approach to cortisone injections for symptomatic osteoarthritis of the knee is more accurate than anteromedial or anterolateral approaches, but there are little data to correlate clinical outcomes with these results. Additionally, there are minimal data to evaluate the pain of such procedures, and this consideration may impact physician preferences for a preferred approach to knee injection.

PURPOSE

To determine the comparative efficacy and tolerability (patient comfort) of landmark-guided cortisone injections at 3 commonly used portals into the arthritic knee without effusion.

STUDY DESIGN

Randomized controlled trial; Level of evidence, 1.

METHODS

Adult, English-speaking patients presenting to a sports medicine clinic with knee pain attributed to radiographically proven grades I through III knee osteoarthritis were randomized to receive a cortisone injection via superolateral, anteromedial, or anterolateral approaches. Patients used a visual analog scale (VAS) to self-report comfort with the procedure. Western Ontario and McMaster Universities Arthritis Index (WOMAC) 3.1 VAS scores were used to establish baseline pain and dysfunction prior to the injection and at 1 and 4 weeks follow-up via mail.

RESULTS

A total of 55 knees from 53 patients were randomized for injection using a superolateral approach (17 knees), an anteromedial approach (20 knees), and an anterolateral approach (18 knees). The mean VAS scores for procedural discomfort showed no significant differences between groups (superolateral, 39.1 ± 28.5; anteromedial, 32.9 ± 31.5; anterolateral, 33.1 ± 26.6; P = .78). WOMAC scores at baseline were similar between groups as well (superolateral, 1051 ± 686; anteromedial, 1450 ± 573; anterolateral, 1378 ± 673; P = .18). The WOMAC scores decreased at 1 and 4 weeks for all groups, with no significant differences in reduction between the 3 groups.

CONCLUSION

Other studies have shown that the superolateral portal is the most accurate. This study did not assess accuracy, but it showed that all 3 knee injection sites studied have similar overall clinical benefit at 4-week follow-up. Procedural pain was not significantly different between groups.

American Medical Society for Sports Medicine position statement: interventional musculoskeletal ultrasound in sports medicine

The use of diagnostic and interventional ultrasound has significantly increased over the past decade. A majority of the increased utilization is by nonradiologists. In sports medicine, ultrasound is often used to guide interventions such as aspirations, diagnostic or therapeutic injections, tenotomies, releases, and hydrodissections. This American Medical Society for Sports Medicine (AMSSM) position statement critically reviews the literature and evaluates the accuracy, efficacy, and cost-effectiveness of ultrasound-guided injections in major, intermediate, and small joints, and soft tissues, all of which are commonly performed in sports medicine. New ultrasound-guided procedures and future trends are also briefly discussed. Based on the evidence, the official AMSSM position relevant to each subject is made.

American Medical Society for Sports Medicine (AMSSM) position statement: interventional musculoskeletal ultrasound in sports medicine

BACKGROUND

The use of diagnostic and interventional ultrasound has significantly increased over the past decade. A majority of the increased utilisation is by non-radiologists. In sports medicine, ultrasound is often used to guide interventions such as aspirations, diagnostic or therapeutic injections, tenotomies, releases and hydrodissections.

OBJECTIVE

Critically review the literature related to the accuracy, efficacy and cost-effectiveness of ultrasound-guided injections (USGIs) in major, intermediate and small joints; and soft tissues.

DESIGN

Systematic review of the literature.

RESULTS

USGIs are more accurate than landmark-guided injections (LMGIs; strength of recommendation taxonomy (SORT) Evidence Rating=A). USGIs are more efficacious than LMGIs (SORT Evidence Rating=B). USGIs are more cost-effective than LMGIs (SORT Evidence Rating=B). Ultrasound guidance is required to perform many new procedures (SORT Evidence Rating=C).

CONCLUSIONS

The findings of this position statement indicate there is strong evidence that USGIs are more accurate than LMGI, moderate evidence that they are more efficacious and preliminary evidence that they are more cost-effective. Furthermore, ultrasound-guided (USG) is required to perform many new, advanced procedures and will likely enable the development of innovative USG surgical techniques in the future.

Where and how to inject the knee--a systematic review

Objectives

The knee can be injected at different anatomic sites with or without image-guidance. We undertook a systematic review to determine the accuracy of intra-articular knee injection (IAKI) and whether this varied by site, use of image-guidance, and experience of injectors, and whether accuracy of injection, site, or use of image-guidance influenced outcomes following IAKIs.

Methods

Medline, Embase, AMED, CINAHL, Web of Knowledge, Cochrane Central Registers for Controlled Trials up to Dec 2012 were searched for studies that evaluated either accuracy of IAKIs or outcomes related to accuracy, knee injection sites, or use of image-guidance. Within-study and between-study analyses were performed.

Results

Data from 23 publications were included. Within-study analyses suggested IAKIs at the superomedial patellar, medial midpatellar (MMP), superolateral patellar (SLP) and lateral suprapatellar bursae sites were more accurate when using image-guidance than when blinded (ranges of pooled risk difference 0.09–0.19). Pooling data across studies suggested blinded IAKIs at the SLP site were most accurate (87%) while MMP (64%) and anterolateral joint line (ALJL) sites were (70%) least accurate. Overall about one in five blinded IAKIs were inaccurate. There was some evidence that experience of the injector was linked with improved accuracy for blinded though not image-guided injections. Based on a small number of studies, short but not longer-term outcomes for ultrasound-guided were found to be superior to blinded IAKIs.

Conclusions

Image-guided IAKIs are modestly more accurate than blinded IAKIs especially at the MMP and ALJL sites. Blinded injections at SLP site had good accuracy especially if performed by experienced injectors. Further studies are required to address the question whether accurate localization is linked with an improved response.

Aspiration and injection of the knee joint: approach portal

Aspiration and injection of the knee joint is a commonly performed medical procedure. Injection of corticosteroid for the treatment of osteoarthritis is the most common reason for knee joint injection, and is performed as an office procedure. Debate exists among practitioners as to the 'best' approach portal for knee injection. This paper examines the various approach portals for injection and/or aspiration of the knee joint, as well as the accuracy of each approach. Searches were made of electronic databases, and appropriate papers were identified and hand-searched. Although there is some evidence that particular approach portals may be more efficacious in the presence of specific knee joint pathologies, generally, in experienced hands, it is of no clinical consequence as to which approach portal is utilised for aspiration or injection of the knee joint. No approach portal is 100% accurate, and the accuracy of injection of the knee joint may be enhanced by the use of techniques such as ultrasound. Practitioners are reminded that they should continuously refine and practice their preferred technique. Knee joint aspiration and injection is a common, simple, and generally safe office procedure.

Prospective randomized clinical trial: single and weekly viscosupplementation

OBJECTIVE:

To compare two different dosages of an intermediate molecular weight sodium hyaluronate (HA) (Osteonil^®-TRB Pharma) assessing whether a single 6 ml application of this HA has the same effectiveness as the classical three-weekly 2 ml dose.

METHODS:

108 patients with knee osteoarthritis were randomized into two groups of 54 patients each. The groups were designated "single" (S) and "weekly" (W). Patients in group S underwent a viscosupplementation procedure by application of only 6 ml of sodium hyaluronate and 1 ml triamcinolone hexacetonide. Patients in group W underwent the procedure of viscosupplementation through three applications with 2 ml sodium hyaluronate with a week interval between them, and the first application was also performed with the infiltration of 1 ml (20 mg) of Triamcinolone Hexacetonide. Both groups were assessed before, at one month and three months after application, by responding to the WOMAC, Lequesne, IKDC and VAS questionnaires.

RESULTS:

There was no statistical difference between the single application of 6 ml of sodium hyaluronate and classic application with three weekly injections. However, only the classical regime showed statistically significant improvement in baseline pain (WOMAC pain and VAS).

CONCLUSION:

Our results suggest that both application schemes improve application function, but the three-weekly regimen of 2 ml was more effective in reducing pain. Level of Evidence I, Prospective Randomized, Clinical Trial.

Randomized prospective study evaluating addition of corticoid to viscosupplementation: three months of follow-up

Objective

To assess if the initial results of viscosupplementation are improved by the addition of corticosteroid.

Design

We evaluated 104 patients receiving usual care for knee osteoarthritis at the Universidade de São Paulo Medical Center. Patients were randomized to receive either a single intra-articular injection of 6 mL of Hylan GF-20 (Group 1) or a single intra-articular injection of 6 mL of Hylan GF-20 plus 1 mL (20 mg) of Triamcinolone Hexacetonide (Group 2). VAS, WOMAC and Lequesne questionnaires were applied at weeks zero (prior the injection), and after one, four, and 12 weeks.

Results

The baseline measurements of the two groups with 52 patients each were not statistically different. At week one, WOMAC and VAS showed significantly better results for Group 2 compared to Group 1 (p < 0,05). At week four the scores did not show a statistically significant differences. The groups showed similar results at week 12.

Conclusion

The addition of Triamcinolone Hexacetonide improves the short term symptom/functional scores of viscosupplementation.

A physiotherapy perspective of musculoskeletal imaging in sport

This paper presents a physiotherapy perspective on the role that imaging is now playing in the diagnosis and management of musculoskeletal and sporting injuries. Although the Royal College of Radiologists and the UK Chartered Society of Physiotherapy were founded in the latter part of the nineteenth century, it is 100 years later that developments in the UK NHS have led to increased roles for non-medical healthcare professionals and allied health professionals, such as physiotherapists, in an extended clinical role. Physiotherapists, perhaps because of their knowledge of clinical and applied anatomy, have keenly taken up the opportunities offered to request and interpret imaging in its various forms; the most commonly available are plain radiography, musculoskeletal ultrasound and MRI. This has meant taking formal courses under the auspices of universities with mentorship and tutoring within the clinical setting, which are part of a continuing professional development. The ability to request several forms of imaging has enhanced physiotherapy practice and has increased the appreciation of the responsibilities which accompany this new role.

Distribution of effusion in knee arthritis as measured by high-resolution ultrasound

Information about the distribution of effusion within the arthritic knee joint should be considered in selecting an anatomical approach for arthrocentesis. We recorded ultrasound measurements of fluid distribution in the knees of patients attending our clinic for knee injections under ultrasound guidance. In a cross-sectional observational study, we used high-resolution ultrasound (US) to record measurements of maximum fluid depth in the medial, midline and lateral regions of the suprapatellar pouch (SPP) in 46 patients with arthritis attending for routine US-guided injection of the knee. Mean fluid depth [in millimetres, (SD)] was significantly greater in the lateral SPP [9.2 (5.1)] than in the medial [6.5 (4.6)] or the midline [5.9 (3.7)] regions with the knee in relaxed full extension (p < 0.001 for comparison of lateral SPP with both midline and medial SPP). Small effusions were more commonly detected in the lateral SPP than elsewhere. In patients with painful knee arthritis, fluid distributes maximally to the lateral SPP in the extended knee. This has implications regarding the anatomical approach to arthrocentesis that clinicians should choose to perform and teach.

A randomized controlled trial evaluating the cost-effectiveness of sonographic guidance for intra-articular injection of the osteoarthritic knee

OBJECTIVE

The present randomized controlled study investigated whether sonographic needle guidance affected the outcomes of intra-articular injection for osteoarthritis of the knee.

METHODS

Ninety-four noneffusive knees with osteoarthritis were randomized to injection by conventional palpation-guided anatomic landmark injection or sonographic image-guided injection enhanced with a 1-handed mechanical (the reciprocating procedure device) syringe. After intra-articular placement and synovial space dilation were confirmed by sonography, a syringe exchange was performed, and 80 mg of triamcinolone acetonide was injected with the second syringe through the indwelling intra-articular needle. Baseline pain, procedural pain, pain at outcome (2 weeks and 6 months), responders, therapeutic duration, reinjection rates, total cost, and cost per responder were determined.

RESULTS

Relative to conventional palpation-guided anatomic landmark methods, sonographic guidance for injection of the knee resulted in 48% reduction in procedural pain (P < 0.001), a 42% reduction in pain scores at outcome (P < 0.03), 107% increase in the responder rate (P < 0.001), 52% reduction in the nonresponder rate (P < 0.001), a 36% increase in therapeutic duration (P = 0.01), a 13% reduction ($17) in cost per patient per year, and a 58% ($224) reduction in cost per responder per year for a hospital outpatient (P < 0.001).

CONCLUSIONS

Sonographic needle guidance reduced procedural pain and improved the clinical outcomes and cost-effectiveness of intra-articular injections of the osteoarthritic knee.

The most accurate approach for intra-articular needle placement in the knee joint: a systematic review

INTRODUCTION

Intra-articular needle placement in the knee joint, such as injection or aspirations, are commonly used for therapeutic, diagnostic, and research purposes. Although several approaches can be used to establish an intra-articular injection or aspiration of the knee joint, the accuracy differs per approach.

OBJECTIVE

To summarize the evidence concerning the accuracy of different approaches for intra-articular needle placements in the knee. Additionally, to assess whether the accuracy of different approaches is related to factors such as underlying disease, severity of underlying disease, approach-related factors, and/or the rate of local reactions.

METHODS

The literature was systemically reviewed until July 2010. Risk of bias of the included studies was assessed by the QUADAS tool. Study characteristics were extracted; accuracy results were pooled per approach.

RESULTS

Nine studies were included. The superolateral approach with the leg in extension was studied most (230 injections) and resulted in the highest pooled accuracy of 91% (95% CI 84-99%). The lateral midpatellar approach, the anterolateral approach, and the anteromedial approach resulted in the lowest pooled accuracy rates, 85% (95% CI 68-100%), 67% (95% CI 43-91%) and 72% (95% CI 65-78%), respectively.

CONCLUSIONS

The superolateral approach was investigated most and resulted in the highest pooled accuracy rate of 91% (95% CI 84-99%). Nevertheless, this approach still results in a substantial amount of extra-articular needle placements. Guidance of intra-articular needle placements by imaging techniques may enhance the accuracy. The costs and extra time associated with these techniques should be taken into consideration.

US-guided injection of the upper and lower extremity joints

There is a growing interest in the application of ultrasound (US) guidance for diagnostic and therapeutic joint injections. US provides direct visualization of soft tissues and the outer borders of bony structures. With real-time needle guidance the success rate of intra-articular injections improves and iatrogenic damage to anatomic structures can be avoided. An US machine is more readily available, transferrable and more affordable than a fluoroscopy machine or CT scanner and lacks the risk of radiation. These factors make US a valuable alternative to procedures performed either blind or under fluoroscopic or CT guidance. This article focuses on the rationale for injections in the upper and lower extremity joints and describes and illustrates the different US-guided injection techniques.

Accuracy of ultrasound-guided and palpation-guided knee injections by an experienced and less-experienced injector using a superolateral approach: a cadaveric study

OBJECTIVES

To evaluate the accuracy of ultrasound (US)-guided and palpation-guided knee injections by an experienced and a less-experienced clinician with use of a superolateral approach.

DESIGN

Single-blinded, prospective study.

SETTING

Academic institution procedural skills laboratory.

PARTICIPANTS

Twenty cadaveric knee specimens without trauma, surgery, or major deformity.

INTERVENTION

US-guided and palpation-guided knee injections of colored liquid latex were performed in each specimen by an experienced and a less-experienced clinician with use of a superolateral approach. The order of injections was randomized. The specimens were subsequently dissected by a blinded investigator and assessed for accuracy.

MAIN OUTCOMES

Accuracy was divided into 3 categories: (1) accurate (all of the injectate was within the joint), (2) partially accurate (some of the injectate was within the joint and some was within the periarticular tissues), and (3) inaccurate (none of the injectate was within the joint). The accuracy rates were calculated for each clinician and guidance method.

RESULTS

US-guided knee injections that used a superolateral approach were 100% accurate for both clinicians. Palpation-guided knee injections that used a superolateral approach were significantly influenced by experience, with the less-experienced investigator demonstrating an accuracy rate of 55% (95% confidence interval = 34%-74%) and the more experienced investigator demonstrating an accuracy rate of 100% (95% confidence interval = 81%-100%).

CONCLUSIONS

US-guided knee injections that use a superolateral approach are very accurate in a cadaveric model, whereas the accuracy of palpation-guided knee injections that use the same approach is variable and appears to be significantly influenced by clinician experience. These findings suggest that US guidance should be considered when one performs knee injections with a superolateral approach that require a high degree of accuracy.

The efficacy, accuracy and complications of corticosteroid injections of the knee joint

PURPOSE

Corticosteroid knee injections are being increasingly used in the conservative management of knee osteoarthritis. The procedure is usually performed in secondary care by orthopaedic surgeons and rheumatologists, but as the role of general practitioners in chronic disease management expands, joint injections are now frequently being performed in primary care. It is commonly perceived amongst clinicians that the benefits of corticosteroid knee joint injections in treating symptomatic knee osteoarthritis significantly outweigh the risks of complications.

METHODS

The evidence in the literature for the benefits, accuracy, safety and complications of corticosteroid knee injections in osteoarthritis is reviewed. The perception that serious complications are rare is addressed, and the incidence of infectious complications is estimated.

RESULTS AND CONCLUSIONS

Short-term symptomatic relief is the only evidence-based benefit of corticosteroid injection of an osteoarthritic knee. Accurate intra-articular placement is not achieved in up to 20% of injections and varies considerably with the anatomical approach used. There is no evidence that a medial approach is more accurate. The incidence of serious infectious complications following knee joint injections ranges widely, and may be as high as 1 in 3,000 and potentially far higher in high-risk patients for whom specialist management is advised.

The highly accurate anteriolateral portal for injecting the knee

Background

The extended knee lateral midpatellar portal for intraarticular injection of the knee is accurate but is not practical for all patients. We hypothesized that a modified anteriolateral portal where the synovial membrane of the medial femoral condyle is the target would be highly accurate and effective for intraarticular injection of the knee.

Methods

83 subjects with non-effusive osteoarthritis of the knee were randomized to intraarticular injection using the modified anteriolateral bent knee versus the standard lateral midpatellar portal. After hydrodissection of the synovial membrane with lidocaine using a mechanical syringe (reciprocating procedure device), 80 mg of triamcinolone acetonide were injected into the knee with a 2.0-in (5.1-cm) 21-gauge needle. Baseline pain, procedural pain, and pain at outcome (2 weeks and 6 months) were determined with the 10 cm Visual Analogue Pain Score (VAS). The accuracy of needle placement was determined by sonographic imaging.

Results

The lateral midpatellar and anteriolateral portals resulted in equivalent clinical outcomes including procedural pain (VAS midpatellar: 4.6 ± 3.1 cm; anteriolateral: 4.8 ± 3.2 cm; p = 0.77), pain at outcome (VAS midpatellar: 2.6 ± 2.8 cm; anteriolateral: 1.7 ± 2.3 cm; p = 0.11), responders (midpatellar: 45%; anteriolateral: 56%; p = 0.33), duration of therapeutic effect (midpatellar: 3.9 ± 2.4 months; anteriolateral: 4.1 ± 2.2 months; p = 0.69), and time to next procedure (midpatellar: 7.3 ± 3.3 months; anteriolateral: 7.7 ± 3.7 months; p = 0.71). The anteriolateral portal was 97% accurate by real-time ultrasound imaging.

Conclusion

The modified anteriolateral bent knee portal is an effective, accurate, and equivalent alternative to the standard lateral midpatellar portal for intraarticular injection of the knee.

Trial Registration

ClinicalTrials.gov: NCT00651625

The outcomes and cost-effectiveness of intraarticular injection of the rheumatoid knee

Although intraarticular injections are important to the management of rheumatoid arthritis, there are few studies regarding the cost-effectiveness of alternative injection techniques. This randomized controlled study addressed the cost-effectiveness of two different low-cost, anatomic landmark palpation-directed intraarticular injection techniques. Ninety-six symptomatic rheumatoid knees were randomized to two different low-cost, palpation-guided intraarticular injection techniques utilizing (1) a conventional syringe or (2) a mechanical syringe, the RPD (the reciprocating procedure device). Three milliliters of 1% lidocaine were used to anesthetize the synovial membrane, followed by arthrocentesis and hydrodissection, and injection of 80 mg of triamcinolone acetonide utilizing the one-needle two-syringe technique. Baseline pain, procedural pain, aspirated fluid volume, pain at outcome (2 weeks and 6 months), responders, reinjection rates, cost/patient/year, and cost/responder/year were determined. Pain was measured with the 10 cm Visual Analogue Pain Scale (VAS). Both techniques significantly reduced pain scores at outcome from baseline (P < 0.001). The mechanical syringe technique resulted in a greater volume of aspirated fluid (P < 0.01), a 38% reduction in procedural pain (P < 0.001), a 24% reduction in pain scores at outcome (P < 0.03), an increase in the responder rate (P < 0.025), 33% increase in the time to next injection (P < 0.001), 23% ($35 US) reduction in cost/patient/year for a patient treated in a physician office (P < 0.001), 24% reduction ($26 US) in cost/patient/year for a hospital outpatient (P < 0.001), and 51% ($151 US) reduction in cost/responder/year (P < 0.001). The outcomes and cost-effectiveness of intraarticular injection of the rheumatoid knee can be improved significantly with low-cost alternations in technique.

A Randomized Controlled Trial of the Cost-Effectiveness of Ultrasound-Guided Intraarticular Injection of Inflammatory Arthritis

Objective.

We studied whether sonographic needle guidance affected the outcomes of intraarticular (IA) injection for inflammatory arthritis.

Methods.

Joints with inflammatory arthritis (n = 244; 76% rheumatoid arthritis, 3% small joints, 51% intermediate, and 46% large) were randomized to injection by conventional palpation-guided anatomic injection (120 joints) or sonographic image-guided injection enhanced with a 1-handed reciprocating procedure device mechanical syringe (124 joints). A 1-needle, 2-syringe technique was used. After IA placement and synovial space dilation were confirmed by sonography, a syringe exchange was performed, and triamcinolone acetonide was injected with the second syringe through the indwelling IA needle. Baseline pain, procedural pain, pain at outcome (2 weeks and 6 months), responders, therapeutic duration, reinjection rates, total cost, and cost per responder were determined.

Results.

Relative to conventional palpation-guided methods, sonographic guidance for injection of inflammatory arthritis resulted in an 81% reduction in injection pain (p < 0.001), 35% reduction in pain scores at outcome (p < 0.02), 38% increase in the responder rate (p < 0.003), 34% reduction in the non-responder rate (p < 0.003), 32% increase in therapeutic duration (p = 0.01), 8% reduction ($7) in cost/patient/year, and a 33% ($64) reduction in cost/responder/year for a hospital outpatient (p < 0.001).

Conclusion.

Sonographic needle guidance improves the performance, clinical outcomes, and cost-effectiveness of IA injections for inflammatory arthritis. (Clinical Trial Identifier NCT00651625)

Viscosupplementation treatment of arthritis pain

With the aging of the baby boomer generation, the number of patients with osteoarthritis (OA) is expected to swell, posing treatment challenges. Viscosupplementation, in which hyaluronic acid (HA) is injected into the knee joint, has evolved into an important part of our current therapeutic regimen in addressing the patient with knee pain due to OA. Although suffering from lack of an "evidence-based" approach, and largely funded by industry, there is a growing body of outcome data demonstrating the efficacy of HA in decreasing pain and improving function in patients with knee OA, although no evidence indicates that HA is in any way chondroprotective. The clinical success of HA has led to the ongoing introduction of various forms of HA, although little data are available to justify one over the other.

Feasibility of sonography for intra-articular injections in the knee through a medial patellar portal

OBJECTIVE

The purpose of this study was to investigate the feasibility of using real-time high-resolution sonography to guide an injection needle into the intra-articular space within the knee.

METHODS

Eighty-nine patients with radiographically confirmed knee osteoarthritis (Kellgren-Lawrence grade 2 or 3) without an effusion were included. After sonographically guided or blind injection of hyaluronic acid (HA) and contrast dye through a medial patellar portal (MPP) into the knee joint, a radiographic image was made to ascertain whether the injected material had reached the intra-articular space.

RESULT

Sonographically guided injections of HA into the knee joint had a significantly greater accuracy rate (95.6%) than blind injections (77.3%; P = .01).

CONCLUSIONS

Intra-articular injections via an MPP using sonographic guidance may raise the accuracy rate in knee joint injections.

Does sonographic needle guidance affect the clinical outcome of intraarticular injections?

OBJECTIVE

This randomized controlled study addressed whether sonographic needle guidance affected clinical outcomes of intraarticular (IA) joint injections.

METHODS

In total, 148 painful joints were randomized to IA triamcinolone acetonide injection by conventional palpation-guided anatomic injection or sonographic image-guided injection enhanced with a one-handed control syringe (the reciprocating device). A one-needle, 2-syringe technique was used, where the first syringe was used to introduce the needle, aspirate any effusion, and anesthetize and dilate the IA space with lidocaine. After IA placement and synovial space dilation were confirmed, a syringe exchange was performed, and corticosteroid was injected with the second syringe through the indwelling IA needle. Baseline pain, procedural pain, pain at outcome (2 weeks), and changes in pain scores were measured with a 0-10 cm visual analog pain scale (VAS).

RESULTS

Relative to conventional palpation-guided methods, sonographic guidance resulted in 43.0% reduction in procedural pain (p < 0.001), 58.5% reduction in absolute pain scores at the 2 week outcome (p < 0.001), 75% reduction in significant pain (VAS pain score > or = 5 cm; p < 0.001), 25.6% increase in the responder rate (reduction in VAS score > or = 50% from baseline; p < 0.01), and 62.0% reduction in the nonresponder rate (reduction in VAS score < 50% from baseline; p < 0.01). Sonography also increased detection of effusion by 200% and volume of aspirated fluid by 337%.

CONCLUSION

Sonographic needle guidance significantly improves the performance and outcomes of outpatient IA injections in a clinically significant manner.

Detection of traumatic arthrotomy of the knee using the saline solution load test

BACKGROUND

The saline solution load test helps to determine if a wound extends into the knee joint. Little is known about the volume of injected intra-articular saline solution that is needed to effectively rule in or rule out a traumatic arthrotomy of the knee. The purpose of the present study was to determine the appropriate volume and needle location for the diagnosis of a traumatic knee arthrotomy and to assess the effect of associated variables, including knee circumference, body mass index, and sex.

METHODS

Fifty-six consecutive patients scheduled for knee arthroscopy were enrolled. A standard inferolateral arthroscopic portal was made with a single stab incision with use of a number-11 blade. Injection sites were randomized to either a superomedial or inferomedial location. The injection of normal saline solution at a rate of 5 mL/sec through an 18-gauge needle was continued while the knee was moved through a range of motion until fluid extravasated from the iatrogenic laceration. The volume of injected fluid was recorded.

RESULTS

The study group included thirty-one female patients and twenty-five male patients with a combined average age of fifty years and an average body mass index of 30.9. In order to effectively diagnose 50% of the arthrotomies, 75 mL of injected fluid was needed; the volumes that were needed in order to effectively diagnose 75%, 90%, 95%, and 99% of the arthrotomies were 110, 145, 155, and 175 mL, respectively. The mean volumes of injected fluid needed for a positive result at the inferomedial and superomedial needle locations were 64.0 and 95.2 mL, respectively; this difference was significant (p = 0.01). There was no correlation between necessary injection volume and sex, body mass index, or knee circumference.

CONCLUSIONS

In order to detect 95% of 1-cm inferolateral arthrotomies of the knee with use of the saline solution load test, 155 mL must be injected. An inferomedial injection location requires significantly less fluid than a superomedial injection location does for the diagnosis of inferolateral arthrotomies of the knee.

A comparison of intra-articular hyaluronan injection accuracy rates between three approaches based on radiographic severity of knee osteoarthritis

OBJECTIVE

To compare the accuracy rates of intra-articular hyaluronic acid (HA) injections for osteoarthritis (OA) of the knee between the modified Waddell approach (an anteromedial approach with manipulative ankle traction at 30 degrees of knee flexion), an anteromedial approach with the subjects seated (hereinafter the seated anteromedial approach) and a lateral patellar approach based on the Kellgren-Lawrence (K-L) radiographic grade (II, III and IV).

DESIGNS

Fifty patients with knee OA received HA injections through the three approaches. The accuracy rates were confirmed with a single radiograph after injections of a mixture of radiographic contrast medium.

RESULTS

In the K-L grade IV cases (n=11), the accuracy rates through the modified Waddell approach (11 out of 11, 100%) were significantly higher than those through the seated anteromedial approach (six out of 11, 55%) and the lateral patellar approach (six out of 11, 55%) (P=0.035). No significant differences were detected in the accuracy rates of the participants classified as grade II (n=21) or III (n=18) cases between the modified Waddell approach (86% and 78%, respectively), the seated anteromedial approach (71% and 56%, respectively) and the lateral patellar approach (86% and 61%, respectively) (P>0.05).

CONCLUSION

Although previous studies have been conducted on the accuracy of needle placement into the intra-articular space of the knee, no evaluations were performed with the results categorized by radiographic severity. This study highlighted the need for clinicians to change the approach employed for HA injections, according to the severity of knee OA.