Introduction to diagnostic musculoskeletal ultrasound: part 2: examination of the lower limb

Inter and intra-examiner reliability of musculoskeletal ultrasound scanning of Anterior Talofibular Ligament and ankle muscles

PURPOSE

Although the function of subjects with chronic ankle instability (CAI) has been examined, structural analysis by ultrasound scanning of the structures surrounding the ankle is limited. Before such structural comparisons between injured and uninjured people can be made it is important to investigate a reliable measurement protocol of structures possibly related to CAI. The aim of this study was to investigate the inter-intra examiner reliability of ultrasonic characteristics of selected structures in healthy subjects.

METHODS

Eleven healthy participants were assessed by an experienced sonographer and inexperienced certificated examiner. Ultrasound images were collected of the ATFL length and ankle muscles of gastrocnemius medialis (GM), tibialis anterior (TA) and peroneals. Thickness was measured for the muscles, whilst cross-sectional area (CSA) was measured for the peroneals. Inexperienced examiner repeated the measurements a week later.

RESULTS

Inter-examiner reliability was excellent for all structures (ICC3,1 = 0.91-0.98). Intra-examiner reliability shows excellent agreement for all structures (ICC3,1 = 0.92-0.98) except GM (good agreement) (ICC3,1 = 0.82). LoA, relative to structure size, ranged from 1.38 to 6.88% for inter-reliability and from 0.07 to 5.79% for intra-reliability.

CONCLUSION

This study shows a high level of inter-intra examiner reliability in measuring the structures possibly related to CAI. Future research has been planned to investigate the structural analysis in CAI by using applied MSUS protocol.

Bedside ultrasound-guided aspiration and corticosteroid injection of a baker's cyst in a patient with osteoarthritis and recurrent knee pain

Baker's cyst accompanying knee osteoarthritis represents a common cause of knee pain presenting to the emergency department. In this case report, a 56-year-old male presented with atraumatic left knee pain and swelling. Radiographically, he had tricompartmental osteoarthritis and was found to have a baker's cyst on duplex ultrasound. Using point-of-care ultrasound, the cyst was aspirated and corticosteroids were injected. The patient tolerated the procedure well and was discharged with a compression wrap and orthopedic follow-up. Baker's cyst aspiration with corticosteroid injection represents a safe alternative treatment option for patients. In some cases, this treatment may be definitive. Orthopedists currently use this procedure to reduce pain and improve function for patients with chronic knee ailments related to baker's cysts. As demonstrated in this case report, implementing this bedside procedure in the emergency department with orthopedic follow-up expands non-surgical, non-narcotic treatment options for patients with chronic knee pain secondary to Baker's cysts with osteoarthritis.

Comparing Point-of-care-ultrasound (POCUS) to MRI for the Diagnosis of Medial Compartment Knee Injuries

Background:

Ultrasound has become an increasingly utilized tool for the imaging of the musculoskeletal system, especially for imaging the components of the knee. Even though MRI is touted as being the golden standard for identifying knee pathologies, the use of ultrasound has gained popularity in this field given its ability for rapid diagnosis. This study aims to investigate the efficacy of point-of-care ultrasound (POCUS) to diagnose injuries to the medial knee compartment when compared to magnetic resonance imaging (MRI).

Methods:

This was a prospective, observational study conducted at an orthopedic outpatient clinic. Prospective patients with medial knee pain scheduled for an MRI of the knee were evaluated by POCUS prior to the MRI. Sonographic findings were then compared to MRI results to assess correlation.

Results:

Nine patients were enrolled in the study. Median age was 53 years and eight were male (89%). POCUS demonstrated 100% sensitivity and 50% specificity for medial meniscus tear and 67% sensitivity and 83% specificity for medial collateral ligament (MCL) tear.

Conclusion:

Ultrasound may have a role as the initial rapid imaging modality in patients with suspected medial meniscus or MCL tears as it is highly sensitive, and it may serve as an effective screening tool for patients with both acute and chronic knee pain.

Ultrasonographic Imaging and Anti-inflammatory Therapy of Muscle and Tendon Injuries Using Polymer Nanoparticles

Ultrasonography is a reliable diagnostic modality for muscle and tendon injuries, but it has been challenging to find right diagnosis of minor musculoskeletal injuries by conventional ultrasonographic imaging. A large amount of hydrogen peroxide (H2O2) are known to be generated during tissue damages such as mechanical injury and therefore H2O2 holds great potential as a diagnostic and therapeutic marker for mechanical injuries in the musculoskeletal system. We previously developed poly(vanillyl alcohol-co-oxalate) (PVAX), which rapidly scavenges H2O2 and exerts antioxidant and anti-inflammatory activity in H2O2-associated diseases. Based on the notion that PVAX nanoparticles generate CO2 bubbles through H2O2-triggered hydrolysis, we postulated that PVAX nanoparticles could serve as ultrasonographic contrast agents and therapeutic agents for musculoskeletal injuries associated with overproduction of H2O2. In the agarose gel phantom study, PVAX nanoparticles continuously generated CO2 bubbles to enhance ultrasonographic echogenicity significantly. Contusion injury significantly elevated the level of H2O2 in skeletal muscles and Achilles tendons. Upon intramuscular injection, PVAX nanoparticles significantly elevated the ultrasound contrast and suppressed inflammation and apoptosis in the contusion injury of musculoskeletal systems. We anticipate that PVAX nanoparticles hold great translational potential as theranostic agents for musculoskeletal injuries.

Allograft tendon reconstruction of the anterior talofibular ligament and calcaneofibular Ligament in the treatment of chronic ankle instability

Background

The purpose was retrospectively to investigate functional and clinical outcomes after anterior talofibular ligament (ATFL) and calcaneofibular ligament (CFL) reconstruction using a single allograft.

Methods

Patients with severe chronic lateral instability of the ankle underwent surgery after conservative treatment failed. Ultrasounds of the ankle were performed, and if the AFTL and CFL were completely torn without enough soft tissue for repair, the ligaments were reconstructed using allograft tendon. Outcomes were assessed by clinical examination, stress radiography, ultrasound, the American Orthopaedic Foot and Ankle Society score (AOFAS), and Karlsson Ankle Functional score (KAFS) before surgery and at final follow-up.

Results

Nineteen patients, ten men and nine women with mean age of 27.9 years (range, 19–41 years), underwent reconstruction. Mean follow-up was 30 months (range, 24–40 months). At final follow-up, all patients had returned to activity without instability, pain, or limited range of motion. On stress radiography, mean talar tilt angle decreased from 17.32° ± 3.58° before surgery to 4.16° ± 1.12° at follow-up (p < 0.001). Mean anterior drawer test (ADT) distance decreased from 9.79 ± 1.01 mm before surgery to 3.97 ± 0.99 mm at follow-up (p < 0.05). Mean AOFAS improved from 64.00 ± 18.43 to 90.32 ± 5.17 points (p < 0.001), and mean KAFS improved from 50.84 ± 16.73 to 90.89 ± 5.08 points (p < 0.001). Ultrasound showed the reconstructed ligaments maintained good continuity and excellent tension. No case of infection and immunological rejection was reported.

Conclusion

This novel reconstruction technique takes into account the anatomical specialty of AFTL and CFL. This case series showed increased stability of the ankle in clinical and functional outcomes.

Trial registration

The trial registration number (TRN) and date of registration: ChiCTR-ORC-17010796, Mar 6th 2017. Retrospectively registered.

Analysis of Pressure Pain Hypersensitivity, Ultrasound Image, and Quality of Life in Patients with Chronic Plantar Pain: A Preliminary Study

OBJECTIVES

To evaluate widespread pressure pain in patients with chronic plantar heel pain compared with that in healthy controls and to investigate the differences in ultrasound imaging and quality of life between these two groups.

METHODS

A total of 22 patients (11 female) with chronic plantar heel pain and the same number of healthy patients, matched according to age and gender, were included in this pilot study. Pressure pain thresholds (PPTs) were bilaterally assessed over the calcaneus bone, the plantar fascia, the first and fifth metatarsals, the soleus muscle, the second metacarpal, and the zygapophyseal joint of C5-C6. Plantar fascia thickness was measured via ultrasound imaging. In addition, quality of life and physical function were assessed using the Short-Form 36 (SF-36) questionnaire and the Foot and Ankle Ability Measure (FAAM) questionnaire, respectively.

RESULTS

Analysis of covariance (ANCOVA) results showed significant differences in the PPTs at all points between the groups (P < 0.001), but not between sides. The PPTs were significantly lower in the patients than in the controls at all sites (P < 0.05). The results showed significant increases in fascia thickness at the calcaneus insertion (group: F = 74.172, P ≤ 0.001; side: F = 8.920, P ≤ 0.001) and the middle fascia point (group: F = 133.685, P = <0.001; side: F = 11.414, P = <0.001) on ultrasound in the patient group compared with the matched control group. The analysis also revealed that the patient group had a significantly lower score on every subscale of the SF-36 and FAAM questionnaires (all P < 0.001), except for the mental component, compared with the matched control group.

DISCUSSION

Patients suffering from chronic plantar heel pain showed widespread and bilateral hypersensitivity, increased thickness of the plantar fascia in the affected foot, and deterioration in quality of life and physical functioning compared with matched controls.

Ultrasonographic tendon alteration in relation to parathyroid dysfunction in chronic hemodialysis patients

OBJECTIVE

To find the nature of tendon involvement in chronic kidney disease (CKD) patients on regular hemodialysis (RD), and its relationship to parathyroid hormone (PTH) level using ultrasonography (US).

METHOD

A total of 50 CKD patients on RD subjected to musculoskeletal examination of knee and ankle, laboratory evaluation, and US of quadriceps tendon and Achilles tendon were involved.

RESULTS

Ankle joint tenderness was the most frequent sign on examination. US of the Achilles tendons showed tenderness during probing in 44% patients, calcific deposition in 24% patients, abnormal peritendon tissue in 20% patients, and abnormal anteroposterior (A-P) middle and distal one-third thicknesses of the Achilles tendon in 20% and 18% patients, respectively. PTH positively correlated with the duration of dialysis, serum phosphorus level, presence of calcific deposit, and increased thickness of the Achilles tendon.

CONCLUSION

The most common ultrasonographic finding in CKD patients on RD was Achilles tendon tenderness during probing. PTH level positively correlated with the duration of dialysis, presence of calcific deposit, and increased thickness of Achilles tendon.

Increased ligament thickness in previously sprained ankles as measured by musculoskeletal ultrasound

CONTEXT

Lateral ankle sprains are among the most common injuries in sport, with the anterior talofibular ligament (ATFL) most susceptible to damage. Although we understand that after a sprain, scar tissue forms within the ligament, little is known about the morphologic changes in a ligament after injury.

OBJECTIVE

To examine whether morphologic differences exist in the thickness of the ATFL in healthy, coper, and unstable-ankle groups.

DESIGN

Cross-sectional study.

SETTING

Laboratory.

PATIENTS OR OTHER PARTICIPANTS

A total of 80 National Collegiate Athletic Association Division I collegiate athletes (43 women, 37 men, age = 18.2 ± 1.1 years, height = 175.8 ± 11.1 cm, body mass = 75.0 ± 16.9 kg) participated in this study. They were categorized into the healthy, coper, or unstable group by history of ankle sprains and score on the Cumberland Ankle Instability Tool.

MAIN OUTCOME MEASURE(S)

A musculoskeletal sonographic image of the ATFL was obtained from each ankle. Thickness of the ATFL was measured at the midpoint of the ligament between the attachments on the lateral malleolus and talus.

RESULTS

A group-by-limb interaction was evident (P = .038). The ATFLs of the injured limb for the coper group (2.20 ± 0.47 mm) and the injured limb for the unstable group (2.28 ± 0.53 mm) were thicker than the ATFL of the "injured" limb of the healthy group (1.95 ± 0.29 mm) at P = .015 and P = .015, respectively. No differences were seen in the uninjured limbs among groups.

CONCLUSIONS

Because ATFL thicknesses of the healthy group's uninjured ankles were similar, we contend that lasting morphologic changes occurred in those with a previous injury to the ankle. Similar differences were seen between the injured limbs of the coper and unstable groups, so there must be another explanation for the sensations of instability and the reinjuries in the unstable group.

A musculoskeletal ultrasound course for physical medicine and rehabilitation residents

Musculoskeletal ultrasound is an imaging modality that can be used to evaluate nerve, tendon, muscle, ligament, and joint disorders and to guide therapeutic procedures. A growing proportion of physiatrists are interested in musculoskeletal ultrasound as demonstrated by the increasing number of musculoskeletal ultrasound articles published in physical medicine and rehabilitation journals and quantity of musculoskeletal ultrasound courses and workshops at physical medicine and rehabilitation conferences. The Mayo Clinic (Rochester, MN) Physical Medicine and Rehabilitation residency program developed a musculoskeletal ultrasound course for their physical medicine and rehabilitation residents, which was implemented in 2008. A detailed description of the course is provided in this article. In addition, results from a premusculoskeletal ultrasound course and postmusculoskeletal ultrasound course practical and written test are presented, and the results of a postmusculoskeletal ultrasound course resident survey are discussed. This information can be used by other physical medicine and rehabilitation residency programs to assist in the creation of their own musculoskeletal ultrasound course.