Synovial plica of the elbow - detailed measurements and how to implicate its relevance in clinical practice.

PURPOSE: The synovial plica of the elbow is a fold of synovial tissue, which is said to be a remnant of the embryonic septa of normal articular development and is located around the radiocapitellar joint. The objective of the present study was to provide morphometric properties of the synovial plica of the elbow and its relation to surrounding structures in asymptomatic patients. METHODS: A retrospective study was conducted to establish the morphometric characteristics of the synovial plica of the elbow. The results of 216 consecutive patients, who for different reasons during the five year period of time underwent magnetic resonance imaging (MRI) of an elbow, were analyzed. RESULTS: Plica was found in a total of 161 of 216 elbows (74.5%). The mean width of the plica was set to be 3.00 mm (SD: 1.39). The mean length of the plica was established at 2.91 mm (SD: 1.13). An analysis of sexual dimorphism was also included. Potential correlations were analyzed for each of the categories and age. CONCLUSIONS: The synovial plica of the elbow is a clinically relevant anatomical structure. Analyzing the morphometric parameters of the synovial plica is necessary to properly evaluate synovial plica syndrome, which can commonly be confused with other sources of lateral elbow pain such as tennis elbow, oppression of the radial and/or posterior interosseous nerve, or snapping of the triceps tendon. The authors suggest that the thickness of the plica may not be the golden diagnostic feature as there are no statistically significant differences in this parameter between symptomatic and asymptomatic patients. A precise and accurate diagnosis of synovial fold syndrome and/or differentiation from other sources of lateral elbow pain must be performed, as the surgical treatment, even if performed properly, will be unsuccessful because of a misdiagnosed source of pain.

The radiocapitellar synovial fold: a lateral anatomic landmark for sizing radial head arthroplasty.

BACKGROUND: Successful radial head arthroplasty relies on reproduction of anatomy. We hypothesized that the radiocapitellar synovial fold could serve as a reference point in radial head prosthesis sizing. Our study aimed to define the relationship between the synovial fold and the radial head in elbows with and without lateral ulnar collateral ligament (LUCL) injury. MATERIALS AND METHODS: We performed magnetic resonance imaging evaluation of 34 elbows to determine the normal relationship between the radiocapitellar synovial fold and the radial head. Next, we used cadaveric dissections to evaluate the anatomic relationships with the LUCL intact and disrupted, as well as in the setting of sizing with a radial head prosthesis. The fold-to-radial head distance (FRHD) was measured on all images and analyzed to determine the relationship of the synovial fold and radial head. RESULTS: The FRHD in cadavers with an intact LUCL and native radial head measured an average of 1.5 mm proximal to the radial head. With the LUCL disrupted and a native radial head, the FRHD measured an average of 1.2 mm proximal to the radial head. The mean difference between the groups was 0.5 mm (P = .031), suggesting that the fold migrated distally in the cadavers with a disrupted LUCL. CONCLUSION: The radiocapitellar synovial fold may be a helpful landmark for radial head sizing. The synovial fold is always just proximal to the articular surface of the radial head. Using this information, the surgeon can prevent overlengthening as the implant should not be placed proximal to the fold.

Prominent synovial plicae in radiocapitellar joints as a potential cause of lateral elbow pain: clinico-radiologic correlation.

BACKGROUND: Thickened synovial plicae in the radiocapitellar joint have been reported as a cause of lateral elbow pain. However, few reports regarding diagnosis based on detailed physical examination and magnetic resonance imaging (MRI) findings are available. The aims of this study were to characterize the clinical manifestations of this syndrome and to investigate the clinical outcomes of arthroscopic surgery. METHODS: We analyzed 20 patients who received a diagnosis of plica syndrome and underwent arthroscopic débridement between 2006 and 2011. The diagnosis was based on physical examination and MRI findings. Elbow symptoms were assessed using a visual analog scale for pain; the Mayo Elbow Performance Index; and the Disabilities of the Arm, Shoulder and Hand score at a minimum of 2 years after surgery. The thickness of plicae on MRI was compared with the normal data in the literature. RESULTS: Plicae were located on the anterior side in 1 patient, on the posterior side in 15, and on both sides in 4. Radiocapitellar joint tenderness and pain with terminal extension were observed in 65% of patients. MRI showed enlarged plicae consistent with intraoperative findings. The mean plica thickness on MRI was 3.7 ± 1.0 mm, which was significantly thicker than the normal value. The mean lengths (mediolateral length, 9.4 ± 1.6 mm; anteroposterior length, 8.2 ± 1.7 mm) were also greater than the normal values. The visual analog scale score for pain decreased from 6.3 to 1.0 after surgery. The Mayo Elbow Performance Index and Disabilities of the Arm, Shoulder and Hand scores improved from 66 to 89 and from 26 to 14, respectively. CONCLUSIONS: Specific findings of the physical examination and MRI provide clues for the diagnosis of plica syndrome. Painful symptoms were successfully relieved after arthroscopic débridement.

Cricoarytenoid Articulation in Elderly Japanese With Special Reference to Morphology of the Synovial Tissue.

OBJECTIVE: To clarify composite fibers and cells in the synovial tissues of the cricoarytenoid joint (CA joint). METHODS: Routine histology and immunohistrochemistry using sagittal or nearly sagittal sections obtained from 18 elderly cadaveric specimens. RESULTS: The CA joint capsule was thin and contained few elastic fibers. A limited supportive ligament, namely, a thickened fascia of the posterior cricoarytenoid muscles, was sometimes evident on the lateral aspect of the CA joint. However, even in the weaker medial aspect of the joint, no marked destruction of the synovial tissues was found. The CA joint always contained synovial folds--a short medial fold and long lateral folds--but these contained no or few macrophages, lymphocytes, and blood capillaries. In 2 exceptional specimens showing inflammatory cell infiltration in the submucosal tissue of the larynx, the macrophage-rich area extended toward the capsule and medial synovial fold. CONCLUSIONS: The lateral aspect of the CA joint was likely to be supported mechanically by the muscle-associated tissues. Strong support of the arytenoid by muscles might reduce the degree of CA joint injury with age. However, some patients with hoarseness due to mucosal inflammation of the larynx might have accompanying synovitis and subsequent cartilage injury in the CA joint.

Synovial Folds Impingement After Unicondylar Knee Arthroplasty.

Soft tissue impingement after total knee arthroplasty has been reported; however, complications after unicondylar knee arthroplasty (UKA) have rarely been reported. We report a rare case of synovial fold impingement that occurred after UKA and caused severe pain with clicking during knee flexion and extension. Diagnostic arthroscopy was performed 3 weeks after UKA and found that a hypertrophied and congested synovial fold in the medial compartment impinged on the femoral component during knee flexion and extension. After excising the synovial fold, the patient's symptoms improved. Synovial fold impingement is a complication that should be considered when patients complain of severe pain with clicking in the knee after UKA.

Synovial plica of the elbow and its clinical relevance.

A synovial plica (fold) is normal anatomic finding, and occurs in 86-100% of cases; however, symptomatic plica is much less common (7.2-8.7% of all elbow arthroscopies).Synovial plica syndrome is a painful elbow condition related to symptomatic synovial plica.Synovial plica syndrome is diagnosed by clinical examination (lateral elbow pain) commonly accompanied by local tenderness, pain at terminal extension and/or painful snapping.Synovial plica syndrome may be mimicked by other elbow conditions, commonly tennis elbow, loose bodies, and degenerative arthritis.Magnetic resonance imaging or ultrasound scan may support diagnosis in correlation with clinical findings, but symptomatic plica may also be diagnosed as unexpected during elbow arthroscopy.The arthroscopic resection is effective and safe if conservative treatment fails. Cite this article: EFORT Open Rev 2020;5:549-557. DOI: 10.1302/2058-5241.5.200027.

Lateral atlantoaxial joint meniscoid volume in individuals with whiplash associated disorder: A case-control study.

BACKGROUND: Lateral atlantoaxial (LAA) joints are established sources of nociceptive input in chronic whiplash associated disorder (WAD). These joints contain intra-articular meniscoids that may be damaged in whiplash trauma. LAA joint meniscoid morphology has not been investigated comprehensively in a chronic WAD population, and it is unclear whether morphological differences exist compared to a pain-free population. OBJECTIVES: This study examined LAA joint meniscoid volume in individuals with chronic WAD who report pain in a distribution consistent with LAA joint pain. DESIGN: Case-control study. METHOD: Fourteen individuals with chronic WAD with pain in an LAA joint distribution (mean [SD] age 38.1 [10.8] years; six female) and 14 age- and sex-matched pain-free controls (38.0 [10.5] years) underwent cervical spine magnetic resonance imaging. LAA joint images were inspected for meniscoids; meniscoid volume was calculated in mm3 and as a percentage of articular cavity volume. Symptom duration, location and intensity were recorded. Data were analysed using paired t-tests, Wilcoxon signed-rank testing, Spearman's rank testing, linear and logistic regression (α < 0.05). RESULTS: Ventral and dorsal meniscoids (n = 112) were found in each LAA joint. Greater dorsal meniscoid volume as a percentage of articular cavity volume was associated with higher pain intensity (odds ratio 1.48, p = 0.03; likelihood ratio test chi-square2 = 6.64, p = 0.04), however no significant differences existed between meniscoid volumes of WAD and control participants. CONCLUSIONS: Findings indicate a potential link between dorsal LAA joint meniscoid volume and pain, suggesting larger meniscoid size may have pathoanatomical significance in WAD.

Synovial tissue morphology of the cricoarytenoid joint in the elderly: a histological comparison with the cricothyroid joint.

We compared the age-related morphology of the cricothyroid (CT) joint with that of the cricoarytenoid (CA) joint using 18 specimens from elderly cadavers in terms of their elastic fiber contents as well as the cells composing the joint capsule and synovial tissues. In contrast to an almost flat-flat interface in the CT joint, the CA joint was similar to a saddle joint. The CA joint capsule was thin and contained few elastic fibers, and in contrast to the CT joint, external fibrous tissues were not exposed to the joint cavity, there being no injury to the CA joint capsule. The lateral and posterior aspects of the CA joint were covered by the lateral and posterior CA muscles, respectively, and the fascia of the latter muscle was sometimes thick with abundant elastic fibers. However, due to possible muscle degeneration, loose connective tissue was often interposed between the fascia and the capsule. The medial and anterior aspects of the CA joint faced loose tissue that was continuous with the laryngeal submucosal tissue. Therefore, in contrast to the CT joint, a definite supporting ligament was usually absent in the CA joint. Synovial folds were always seen in the CA joint, comprising a short triangular mass on the posterior side and long laminar folds on the anterior side. The synovial folds usually contained multiple capillaries and a few CD68-positive macrophages. High congruity of the CA joint surfaces as well as strong muscle support to the arytenoid cartilage appeared to provide the specific synovial morphology.

The cricothyroid joint in elderly Japanese individuals.

Using 15 cricothyroid joint (CT joint) specimens obtained from donated cadavers of elderly individuals, we examined the morphologies of the ceratocricoid ligaments as well as the synovial tissue. The ligaments consistently contained abundant elastic fibers: the fibers tended to be straight on the anterior side in contrast to a mesh-like arrangement on the posterior side. Thick and/or long synovial folds were often evident in the CT joint. The synovial tissue usually contained CD68-positive macrophages, but the positive cells were often restricted to certain parts of the tissue. Factor VIII-positive capillaries were present but few in number, and CD3- or IgM-positive lymphocytes were absent in the synovial tissue. Degenerative changes in the joint cartilage, such as roughness or thinning, were often present, but no cartilage defects were evident. Therefore, in contrast to the small, non-weight-bearing joints of the musculoskeletal system, we considered the degeneration of the CT joint to be a specific, silent form of osteoarthritis. For high-pitched phonation and ossification of the laryngeal cartilage, the CT joint in elderly individuals seemed to maintain its anterior gliding and rotation with the aid of elastic fiber-rich tissues compensating for the loss of congruity between the joint cartilage surfaces.

Morphology of Cervical Spine Meniscoids in Individuals With Chronic Whiplash-Associated Disorder: A Case-Control Study.

Study Design Case-control study. Background Cervical spine meniscoids are thought to contribute to neck pain and hypomobility in individuals with chronic whiplash-associated disorder (WAD); however, their morphology has not been studied in a clinical population. Objectives To investigate cervical spine meniscoid morphology in individuals with chronic WAD. Methods Twenty volunteers with chronic WAD (mean ± SD age, 39.3 ± 11.0 years; 10 female) and 20 age- and sex-matched controls (age, 39.1 ± 10.6 years) underwent cervical spine magnetic resonance imaging. Lateral atlantoaxial and zygapophyseal joints (C2-3 to C6-7) were inspected for meniscoids. Length of meniscoid protrusion was measured and composition (adipose/fibrous/fibroadipose) assessed. Data were analyzed using Wilcoxon signed-rank tests and linear and logistic regression (P<.05). Results Meniscoids were identified in the chronic WAD (n = 317) and control (n = 296) groups. At the lateral atlantoaxial joints, median meniscoid length was greater in the control group (ventral, 6.07 mm; dorsal, 7.24 mm) than the WAD group (ventral, 5.01 mm; P = .06 and dorsal, 6.48 mm; P<.01). At the dorsal aspect of zygapophyseal joints, meniscoids were more frequently fibrous in the chronic WAD group (odds ratio = 2.38, P<.01; likelihood ratio test: χ22, 9.02; P = .01). Conclusion In individuals with chronic WAD, lateral atlantoaxial meniscoids were shorter and dorsal cervical zygapophyseal meniscoids were more fibrous, suggesting alterations in meniscoid composition. This may have pathoanatomical implications in chronic WAD. J Orthop Sports Phys Ther 2016;46(10):902-910. Epub 3 Sep 2016. doi:10.2519/jospt.2016.6702.

Immunohistochemical investigation of nerve fiber presence and morphology in elderly cervical spine meniscoids.

BACKGROUND CONTEXT: Innervation of anatomical structures is fundamental to their capacity to generate nociceptive impulses. Cervical spine meniscoids are hypothesized to be contributors to neck pain; however, their innervation is not comprehensively understood. PURPOSE: This study aimed to examine the presence and morphology of nerve fibers within cervical spine meniscoids and adjacent joint capsules. STUDY DESIGN: This is a cross-sectional study. PATIENT SAMPLE: The sample consists of cervical hemispines of 12 embalmed cadavers (mean [standard deviation] age 82.9 [6.5] years, six female, six left). Either the right or the left half of the cervical spine (hemispine) of each cadaver was included in the sample. So six left sides and six right sides of the cadaver cervical spines made up the 12 hemispines that formed the sample. METHODS: Cervical spine meniscoids and adjacent joint capsules were excised from lateral atlantoaxial and cervical zygapophyseal (C2-C3 to C6-C7) joints (n=67), then paraffin embedded. Meniscoids were sectioned sagittally (5 µm), slide mounted, and immunohistochemistry was performed using primary antibodies to neurofilament heavy (NF-H) and pan-neurofilament (Pan-NF) to identify nerve tissue. The study was supported by institutional graduate student funding. The authors have no conflicts of interest to declare. RESULTS: Seventy-seven meniscoids (23 lateral atlantoaxial, 54 cervical zygapophyseal) were extracted and processed (154 sections in total). Sixty-four individual nerve fiber bundles were identified (26 NF-H positive, 38 Pan-NF positive) from 14 meniscoids. Nerves immunoreactive to both NF-H and Pan-NF were identified in 13 of 77 meniscoids (10 of 14 lateral atlantoaxial joint) from 11 joints (eight cadavers). Nerves were always located in joint capsules except three exclusively Pan-NF immunoreactive nerve fiber bundles from two adipose meniscoids. CONCLUSIONS: The low nerve prevalence in elderly cervical spine meniscoids, with nerves only found in two adipose type meniscoids, suggests these structures may play a minimal role in cervical nociception generation in this demographic. The joint capsules, which were more frequently innervated, appear to be more likely generators of nociception in the elderly. Joint capsule nerves were mostly NF-H positive, indicating potential Aδ-fiber presence.

Synovial tissue morphology of the cricoarytenoid joint in the elderly: a histological comparison with the cricothyroid joint / 대한해부학회지

We compared the age-related morphology of the cricothyroid (CT) joint with that of the cricoarytenoid (CA) joint using 18 specimens from elderly cadavers in terms of their elastic fiber contents as well as the cells composing the joint capsule and synovial tissues. In contrast to an almost flat-flat interface in the CT joint, the CA joint was similar to a saddle joint. The CA joint capsule was thin and contained few elastic fibers, and in contrast to the CT joint, external fibrous tissues were not exposed to the joint cavity, there being no injury to the CA joint capsule. The lateral and posterior aspects of the CA joint were covered by the lateral and posterior CA muscles, respectively, and the fascia of the latter muscle was sometimes thick with abundant elastic fibers. However, due to possible muscle degeneration, loose connective tissue was often interposed between the fascia and the capsule. The medial and anterior aspects of the CA joint faced loose tissue that was continuous with the laryngeal submucosal tissue. Therefore, in contrast to the CT joint, a definite supporting ligament was usually absent in the CA joint. Synovial folds were always seen in the CA joint, comprising a short triangular mass on the posterior side and long laminar folds on the anterior side. The synovial folds usually contained multiple capillaries and a few CD68-positive macrophages. High congruity of the CA joint surfaces as well as strong muscle support to the arytenoid cartilage appeared to provide the specific synovial morphology.