Isolated Complete Distal Biceps Femoris Tendon Tears: Case Series and Literature Review

The Biceps femoris is a vital component of the posterolateral corner of the knee. We report two cases of isolated rupture of the biceps femoris, discuss the possible mechanism of injury, and review the literature.

Does the Interval Slide Procedure Reduce Supraspinatus Tendon Repair Tension?: A Biomechanical Cadaveric Study

Background: The benefits of the interval slide (IS) procedure in retracted rotator cuff tears remain controversial. Purpose: The purpose was to evaluate the effect of the IS procedure on repair tension (RT). It was hypothesized that the IS procedure (anterior IS [AIS], posterior IS [PIS], and intra-articular capsular release [CR]) would reduce the RT of a supraspinatus tendon. Study Design: Controlled laboratory study. Methods: A total of 31 Thiel-embalmed human cadaveric shoulders (mean age, 74 years; range, 68-84 years) were tested. Full-thickness supraspinatus tendon tears were created, and 1 cm of tendon was resected to simulate a retracted defect. Shoulders were randomized into intervention (n = 16) and control (n = 15) groups. In all shoulders, the load during tendon reduction to footprint was measured, an endpoint was defined as maximum tendon lateralization before 50 N was reached, and the RT (load during lateralization to endpoint) of the native tendon (t1) was evaluated. In the intervention group, AIS (t2), PIS (t3), and CR (t4) were performed in order, with RT measurement after each step. In the control group, RT was assessed at the same time points without the intervention. Results: A complete reduction of the tendon was not achieved in any of the shoulders. Mean maximum lateralization was 6.7 ± 1.30 mm, with no significant differences between groups. In the intervention group, the overall IS procedure reduced RT about 47.0% (t1 vs t4: 38.7 ± 3.9 vs 20.5 ± 12.3 N; P < .001). AIS reduced RT significantly (t1 vs t2: 38.7 ± 3.9 vs 27.4 ± 10.5 N; P < .001), whereas subsequent PIS (t2 vs t3: 27.4 ± 10.5 vs 23.2 ± 12.4 N; P = .27) and CR (t3 vs t4: 23.2 ± 12.4 vs 20.5 ± 12.3 N; P = .655) did not additionally reduce tension. Comparison between groups at t4 revealed a reduction of RT of about 47.8% (control vs intervention: 39.3 ± 4.0 vs 20.5 ± 12.3 N; P < .001). Conclusion: The IS procedure reduces RT of the supraspinatus tendon in human cadaveric shoulders. However, performing PIS and CR subsequent to AIS does not reduce tension additionally. Clinical Relevance: These findings provide surgeons with a biomechanical rationale regarding the efficacy of the IS procedure.

Myotendinous pseudomasses: an imaging review

A mass or a tumor may not always be an underlying cause for a clinically apparent swelling. A wide range of myotendinous disorders can present as pseudomasses. These include muscle/myofascial hernia, tendon tears, benign hypertrophy, accessory muscles, tendon xanthomas, diffuse myositis, and exertional compartment syndromes. We have briefly reviewed these lesions highlighting their typical radiological findings and have also highlighted the role of different imaging modalities and the role of dynamic imaging. Although rare, radiologists should be aware of these entities to avoid mislabeling a pseudomass as a mass or malignancy and to detect the abnormality in not-so-apparent masses.

Identifying Key Factors Associated with Subscapularis Tendon Tears and Developing a Risk Prediction Model to Assist Diagnosis

Background: Subscapularis (SSC) tendon tears can cause pain and restricted motion of the shoulder, but accurate diagnosis of this lesion on magnetic resonance imaging (MRI) is challenging, especially in small and partial tears. There are no studies that have established a method to reliably assess the risk of subscapularis tendon tears.Methods: Data on 460 patients who received shoulder arthroscopic surgery with preoperative shoulder MRI were collected retrospectively. Of these, patients with SSC tendon tears were defined as the SSC tear group, and patients with intact subscapularis tendon were enrolled in the non-SSC tear group. Logistic regression analysis was used to identify the risk factors of SSC tendon tears which were then incorporated into the nomogram. Results: Among 22 candidate factors, five independent factors including coracohumeral distance CHD (oblique sagittal) (OR, 0.75; 95%CI, [0.67-0.84]), fluid accumulation (Y-face) (OR, 2.29; 95%CI, [1.20-4.38]), long head of biceps tendon (LHB) dislocation/subluxation (OR, 3.62; 95%CI, [1.96-6.68]), number of posterosuperior (PS) rotator cuff tears (OR, 5.36; 95%CI, [3.12-9.22]), and MRI diagnosis (OR, 1.88; 95%CI, [1.06-3.32]) were identified as key predictors associated with subscapularis tendon tears. Incorporating these predictors, the nomogram achieved a good C index with a good agreement on the risk estimation of calibration plots. Higher total points of the nomogram were associated with a greater risk of subscapularis tendon tears. Conclusion: The diagnostic accuracy of conventional 3.0-T MRI for SSC tendon tears was insufficient. Our study revealed critical predictors associated with subscapularis tendon tears. When evaluating the severity of subscapularis tendon injury, more attention should be paid to these tear-related factors. We developed and validated s satisfactory prediction model to improve the diagnostic performance of MRI which was convenient for clinicians to reach a consensus on risk assessment and identify the SSC tendon tears.

Diagnostic Accuracy of Ultrasonography for Rotator Cuff Tears: A Systematic Review and Meta-analysis

Background: With recent improvements in transducer strength, image resolution, and operator training, ultrasound (US) provides an excellent alternative imaging modality for the diagnosis of rotator cuff tears. Purpose: To evaluate the diagnostic accuracy of US for partial- and full-thickness rotator cuff tears and biceps tendon tears, compare diagnostic values with those of magnetic resonance imaging (MRI) using arthroscopy as the reference standard, assess longitudinal improvements in accuracy, and compare diagnostic values from operators with different training backgrounds. Study Design: Systematic review; Level of evidence, 3. Methods: The PubMed and Cochrane Library databases were systematically searched for full-text journal articles published between January 1, 2010, and April 1, 2020. The inclusion criteria were studies that evaluated the diagnostic accuracy of US for rotator cuff tears or biceps tendon tears utilizing arthroscopy as the reference standard. The exclusion criteria were studies with <10 patients, studies including massive tears without reporting diagnostic data for specific tendons, and studies lacking diagnostic outcome data. Extracted outcomes included diagnostic accuracy, sensitivity, specificity, negative predictive value, and positive predictive value. The mean difference and 95% confidence interval were calculated for both US and MRI diagnostic values, and meta-analysis was conducted using the Mantel-Haenszel random-effects model. Results: In total, 23 eligible studies involving 2054 shoulders were included. US demonstrated a higher median diagnostic accuracy for supraspinatus tendon tears (0.83) and biceps tendon tears (0.93) as compared with subscapularis tendon tears (0.76). US was found to have a higher median accuracy (0.93) for full-thickness supraspinatus tears than partial-thickness tears (0.81). US had superior median sensitivity for partial-thickness supraspinatus tears when performed by radiologists as opposed to surgeons (0.86 vs 0.57). Meta-analysis of the 5 studies comparing US and MRI demonstrated no statistically significant difference in diagnostic sensitivity, specificity, or accuracy for any thickness supraspinatus tears (P = .31-.55), full-thickness tears (P = .63-.97), or partial-thickness tears ( P = .13-.81). Conclusion: For experienced operators, US is a highly sensitive and specific diagnostic modality for the diagnosis of supraspinatus tears and demonstrates statistically equivalent capability to MRI in the diagnosis of both full- and partial-thickness rotator cuff tears.

The Potential Role of Human Derived Amniotic Membrane Graft in The Repair of Induced Tendon Tear in Adult Male Albino Rat: Histological Study

Introduction Achilles tendon tears cause severe impairment in patient mobility and productivity, causing significant reduction in the quality of life. Many complications are associated with the tendon healing process such as peritendinous adhesions and excessive fibrotic scars. Unsatisfactory results appeared with the existing medical and surgical treatments to regain full tendon structure and function. Amniotic membrane is avascular, and characterized by low immunogenicity, anti-inflammatory, antiscarring properties. These criteria render it as a natural biological substitute and a novel therapeutic alternative for tendon tears. Aim: The aim of the work was to study the effect of human amniotic membrane graft application on the repair of induced Achilles tendon tear. Material and methods Fresh human amniotic membrane (AM) grafts were prepared from harvested human full-term caesarian sections-delivered placentas. Thirty adult male albino rats were divided into 3 equal groups (n = 10); group I (control group), group II (tendon tear group) and group III (AM treated group). After anesthesia, a full thickness transverse incision was induced in the rat right Achilles tendons of group II and III. Human derived amniotic membrane graft measuring 1 cm2 was applied circumferentially on the tendon tear in group III. Rats were sacrificed after 28 days. Results After the tendon tear, the untreated group (II) showed gradual accumulation of fat cells replacing the collagen bundles in focal areas. Areas of mononuclear cellular infiltration were demonstrated. The AM-treated group showed many thick parallel regularly arranged collagen fibers with a significant increase in the collagen fibers area percentage. It also showed apparent increase in tenoblasts with regular organization and apparent decrease of mononuclear inflammatory cells. Conclusion This study demonstrated the potential therapeutic role of the application of human amniotic membrane grafts in the repair of Achilles tendon tears, suggesting a future alternative therapy for patients suffering from Achilles tendon tears.

Preoperative Gait Analysis of Peroneal Tendon Tears

Background: Little is known regarding the impact of peroneal tendon tears on function. This study quantifies gait changes associated with operatively-confirmed peroneal tendon tears. Methods: Sixty-five patients with unilateral peroneal tendon tears were prospectively evaluated using preoperative 3D multisegment gait analysis of both limbs. Data were analyzed according to pattern/severity of tears, as confirmed surgically: peroneus brevis tears, reparable (PBR); peroneus brevis tears, irreparable (PBI); peroneus longus tears, irreparable (PLI); and concomitant irreparable tears of both tendons (PBI+PLI). The following parameters were analyzed: ankle sagittal motion, coronal motion, axial rotation, foot progression angle, sagittal power, sagittal moment. Results: Twelve patients (18.5%) had the PBR pattern, 37 (56.9%) PBI, 10 (15.4%) PLI, and 6 (9.2%) PBI+PLI. Compared with the contralateral, nonpathologic extremities, limbs with peroneal tears had diminished ankle sagittal motion (mean 23.14 vs 24.30 degrees, P = .012), ankle/hindfoot axial rotation (6.26 vs 7.23 degrees, P = .001), sagittal moment (1.16 vs 1.29 Nm/kg, P < .001), and sagittal power (1.24 vs 1.47 W/kg, P < .001). The most severe tear patterns had the greatest derangements in multiple parameters of gait (PBI+PLI > PBI or PLI > PBR). For example, all groups except PBR had loss of ankle sagittal moment and/or power in the affected limb, and the greatest losses in moment and power were in the PBI+PLI group (1.22 vs 0.91 Nm/kg, P = .003 for moment; 0.73 vs 1.31 W/kg, P < .001 for power). The PBI+PLI group had a >10-degree varus shift in coronal motion on the affected side ( P = .002). Conclusion: This is the first study to demonstrate diminished biomechanical function in patients with peroneal tendon tears. In vivo 3-dimensional gait analysis found significant changes in hindfoot motion, ankle motion, and ankle power. Impairments were related to the pattern and severity of the tears, and demonstrated a strong association of peroneal tendon tears with diminished ankle plantarflexion strength. Level of Evidence: Level III, retrospective cohort study.