Which morphologies of synovial folds result from degeneration and/or aging of the radiohumeral joint: an anatomic study with cadavers and embryos

The radiohumeral synovial plica: anatomy, histology, and implications in chronic lateral epicondylitis

OBJECTIVES

Our study aimed to elucidate synovial plica (SP) of the elbow histological characteristics and the anatomical relationship with adjacent structures. Subsequently, we sought to assess the relationship between SP and clinical symptoms as well as magnetic resonance imaging (MRI) features in patients with chronic lateral epicondylitis.

METHODS

MRI was performed on eight cadaveric elbows specimens. The MRI findings were compared with those in anatomic sections and histologic preparations. In addition, ninety-nine patients with chronic lateral epicondylitis who underwent preoperative elbow MRI and arthroscopic surgery were included. The patients were divided into SP and without SP groups. The differences in clinical symptoms and MRI features between the two groups were compared.

RESULTS

SP is located proximal to the annular ligament that extends into the joint cavity, then moves to the lateral collateral ligament (LCL) complex, and finally attaches to the lateral epicondyle of the elbow along with the common extensor tendon (CET). The SP, ligament, and tendon blend imperceptibly without distinct boundaries. Furthermore, in a study of patients with chronic lateral epicondylitis, we found that compared to the without SP group, patients in the SP group had higher preoperative and 3-week postoperative VAS scores and more severe abnormalities in LCL complex and CET.

CONCLUSION

The SP is distinct from the annular ligament and closely correlates with the LCL complex and CET enthesis at the lateral epicondyle. Chronic lateral epicondylitis patients with SP have more severe abnormalities of the LCL complex and CET, more severe pain, and longer postoperative recovery times.

KEY POINTS

Question Synovial plica (SP) cause lateral elbow pain, but few studies regarding histological and imaging features of SP and its relationship to chronic lateral epicondylitis exist. Findings The presence of SP leads to more severe common extensor tendon abnormalities and higher visual analog scale scores in patients with chronic lateral epicondylitis. Clinical relevance The combination of magnetic resonance imaging and clinical symptoms to further understand the effect of SP on the clinical symptoms and postoperative recovery in chronic lateral epicondylitis can help refine treatment strategies and improve the prognosis of patients.

Lateral collateral ligament complex insufficiency in recalcitrant lateral epicondylitis: MRI evaluation with arthroscopic findings

PURPOSE

To evaluate the concomitant pathology in recalcitrant LE using MRI with arthroscopic finding correlation.

METHODS

A total of 49 patients were diagnosed with chronic recalcitrant LE and divided into two: LCL complex-intact and LCL complex-involved groups by evaluating MRI as confirmed by a radiologist. Patient information for the history of steroid injection and symptom duration was extracted from the medical records. Arthroscopic images taken during arthroscopic extensor carpi radialis brevis release were evaluated to assess the quality of lateral capsule and concomitant plica.

RESULTS

A total of 24 and 25 patients were included in the LCL-intact and LCL-involved groups, respectively. Among them, seven had complete RCL tears recorded in the LCL-involved group. Symptom duration (15 ± 9 vs. 22 ± 13, p = 0.029) and the number of steroid injections (3 ± 2 vs. 5 ± 3, p = 0.040) were significantly higher in the LCL-involved group than that in the LCL-intact group. A capsular tear was detected for 5 (20%) patients in the LCL-intact and 14 (56%) in the LCL-involved group (p = 0.027). Concomitant plica was observed in 15 (62%) patients in LCL-intact and seven (28%) in the LCL-involved group (p = 0.015). RC joint widening was observed in four patients in the LCL-involved group.

CONCLUSION

The recalcitrant LE is highly a concomitant pathology including LCL complex insufficiency and pathologic elbow plica lesion. The risk factors of LCL insufficiency associated with refractory LE may include multiple steroid injections. Arthroscopic finding such as capsular tears and elbow drive-through signs can be suspected signs for LCL complex insufficiency.

The Usefulness of Dynamic Ultrasonography in Nursemaid's Elbow: A Prospective Case Series of 13 Patients Reconsideration of the Pathophysiology of Nursemaid's Elbow

BACKGROUND

Nursemaid's elbow is a common musculoskeletal disorder among children under 5 years of age. However, diagnostic imaging to confirm a nursemaid's elbow diagnosis is still unavailable. Through the use of a high-frequency ultrasound probe, we determined the etiology and possible pathophysiology of nursemaid's elbow.

METHODS

Thirteen consecutive patients with the clinical suspicion of nursemaid's elbows were examined. A high-frequency linear array 6 to 24 MHz hockey stick transducer was used to detect small changes (partial eclipse signs) of the radial head in the axial view before and after manipulation.

RESULTS

All patients in this study had a successful reduction. A partial eclipse sign was found in all patients before reduction and disappeared after successful reduction.

CONCLUSION

These pathologic features detected through high-frequency ultrasonography suggest the role of the escaped posterior synovial fringe in the pathogenesis of the nursemaid's elbow. The specific finding of a "partial eclipse sign" could be a useful additional clue leading to the correct diagnosis of the nursemaid's elbow and may help avoid the unnecessary reduction in patients who do not have a "partial eclipse sign".

LEVEL OF EVIDENCE

Level II, diagnostic studies.

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 elbow plica: a systematic review of terminology and characteristics

BACKGROUND

There has been a lack of evidence regarding the structure of the elbow plica, or synovial fold. Inconsistency remains regarding the correct terminology, prevalence, and investigation used to understand this anatomic structure.

METHODS

For this systematic review, we searched the PubMed, Ovid-MEDLINE, Cochrane, Google Scholar, and Embase databases using keywords as well as medical subject headings for English-language studies. We conducted a systematic review using the Preferred Reporting Items for Systematic Reviews and Meta-analyses guidelines.

RESULTS

We included 27 articles in this review. "Plica" was the most commonly used terminology (33%). The prevalence of plicae in asymptomatic and symptomatic patients was 77% and 97%, respectively. Provocative factors were sporting activities (57%), including those performed by professional athletes, and heavy labor (43%). Lateral elbow pain represented the most common symptom (49%). Magnetic resonance imaging was the most commonly used diagnostic modality (64%). On the magnetic resonance imaging scans of symptomatic patients, the most common location of the plica was the posterolateral region (54%) and its thickness was a minimum of 3 mm. In 2 studies that included symptomatic patients, the plica was found to cover more than one-third of the radial head.

CONCLUSION

Plicae are prevalent in both asymptomatic and symptomatic patients. Consideration of the pathologies associated with an elbow plica helped identify the following: (1) its thickness is >3 mm and (2) its location is in the posterolateral aspect and/or it covers more than one-third of the radial head quadrant.

Fetal cervical zygapophysial joint with special reference to the associated synovial tissue: a histological study using near-term human fetuses

Human fetal cervical vertebrae are characterized by the large zygapophysial joint (ZJ) extending posteriorly. During our recent studies on regional differences in the shape, extent, and surrounding tissue of the fetal ZJ, we incidentally found a cervical-specific structure of synovial tissues. This study aimed to provide a detailed evaluation of the synovial structure using sagittal and horizontal sections of 20 near-term fetuses. The cervical ZJ consistently had a large cavity with multiple recesses at the margins and, especially at the anterior end, the recess interdigitated with or were located close to tree-like tributaries of the veins of the external vertebral plexus. In contrast to the flat and thin synovial cell lining of the recess, the venous tributary had cuboidal endothelial cells. No or few elastic fibers were identified around the ZJ. The venous-synovial complex seems to be a transient morphology at and around birth, and it may play a role in the stabilization of the growing cervical ZJ against frequent spontaneous dislocation reported radiologically in infants. The venous-synovial complex in the cervical region should be lost and replaced by elastic fibers in childhood or adolescence. However, the delayed development of the ligament flavum is also likely to occur in the lumbar ZJ in spite of no evidence of a transient venous-synovial structure. The cuboidal venous endothelium may simply represent the high proliferation rate for the growing complex.

Systematic Review of the Surgical Outcomes of Elbow Plicae

Background:

Surgical resection is usually required for symptomatic elbow plicae that have failed nonoperative therapy. However, evidence of surgical outcomes has not been presented.

Purpose:

To review the surgical outcomes for the treatment of synovial plicae in the radiocapitellar joint.

Study Design:

Systematic review; Level of evidence, 4.

Methods:

We searched the PubMed, Ovid/MEDLINE, Cochrane Library, Google Scholar, and Embase databases using keywords as well as Medical Subject Headings terms and Emtree ([(elbow OR humeroradial joint OR radiohumeral joint) AND (meniscus OR plica)] OR snapping elbow OR snapping triceps OR synovial fold syndrome OR synovial fringe) for English-language studies. We conducted a systematic review using PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines.

Results:

A total of 14 articles comprising four level 5 and ten level 4 studies were identified, including 279 patients (284 elbows). The triggering factors reported for 58 patients were heavy labor (29 patients; 50.0%), sporting activities (17 patients; 29.3%), and nonspecific trauma (12 patients; 20.7%). Overall, 92 patients (33.0%) were administered a steroid injection before surgery. Arthroscopic plica resection was performed in 266 patients (95.3%). Intraoperatively, plicae were mostly found in the posterior (44.0%) and posterolateral (28.6%) sites, and chondromalacia of the radial head was observed in 25 patients (9.2%). Of the reported surgical outcomes, 67.7% showed a resolution of symptoms. However, 9.3% of patients had residual symptoms, which were likely associated with pre-existing radial head chondromalacia. The complication rate was reported as 1.8%.

Conclusion:

Symptomatic elbow plicae were mostly treated arthroscopically, with most of the results being favorable. Pre-existing chondromalacia and the underestimation of concomitant intra-articular abnormalities may yield an inferior outcome.

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

Arthroscopic Modified Bosworth Procedure for Refractory Lateral Elbow Pain With Radiocapitellar Joint Snapping

Background:

Radiocapitellar joint snapping due to the presence of synovial plica has been described as a contributory intra-articular pathology of lateral epicondylitis (LE).

Hypothesis:

The arthroscopic modified Bosworth technique can provide a safe and favorable outcome for refractory LE with radiocapitellar snapping.

Study Design:

Case series; Level of evidence, 4.

Methods:

Patients treated with the arthroscopic modified Bosworth procedure for refractory LE with radiocapitellar joint snapping were included in this study. The sequential surgical procedures included excision of the upper portion of the anterolateral annular ligament, removal of the synovial plicae, and release of the extensor carpi radialis brevis for all patients. Clinical outcomes were measured at a minimum 1-year follow-up.

Results:

A total of 22 patients with a mean ± SD age of 51.2 ± 10.4 years were included in this study. The mean follow-up was 29.4 ± 7.7 months (range, 21-42 months). The overall visual analog scale score (from preoperative to final follow-up) was 7.5 ± 1.2 vs 2.5 ± 1.8 (P < .001); flexion-extension motion arc was 133.8° ± 11.2° vs 146.4° ± 7.1° (P = .001); pronation-supination motion arc was 101.8° ± 9.2° vs 141.7° ± 10.2° (P = .001); Disabilities of the Arm, Shoulder and Hand score was 54.5 ± 13.2 vs 3.6 ± 4.1 (P < .001); and Mayo Elbow Performance Score was 51.9 ± 12.2 vs 84.3 ± 10.3 (P < .001).

Conclusion:

Radiocapitellar joint snapping may coexist with LE as a disease spectrum. The arthroscopic modified Bosworth technique provides safe and favorable outcomes for patients with refractory LE associated with radiocapitellar joint snapping.

A Comprehensive Review of Radiohumeral Synovial Plicae for a Correct Clinical Interpretation in Intractable Lateral Epicondylitis

PURPOSE OF REVIEW

Radiohumeral synovial plicae (RHSP) have been studied by different authors in different ways; in spite of this, the evidence is poor and the results are controversial and inconclusive even when it comes to referring to this elbow structure. The aim of this article is to review the embryologic development, anatomy and histology, pathophysiologic features, clinical manifestations, physical examination, imaging findings, and treatment of radiohumeral synovial plicae, for their correct clinical interpretation in patients with intractable lateral epicondylitis.

RECENT FINDINGS

Radiohumeral synovial plicae syndrome (RHSPS) can cause intractable lateral epicondylitis and can be easily confused with other clinical conditions affecting the elbow. Many clinicians are not familiar with radiohumeral synovial plica syndrome since there are not many studies about it and previous reports do not seem to reach a consensus. Although its role in elbow injuries and epicondylitis is accepted and its surgical treatment is effective, there is no clear consensus about clinically relevant aspects. RHSP are remnants of normal embryo development of the articular synovial membrane with different anatomical locations, size and shape. Traumatism or overuse can turn RHSP into symptomatic structures at any age and can be compressed between the radial and humeral heads during movement. This compression can cause pain and other symptoms such as snapping, catching, mobility restriction, pitching, clicking, locking, blockage, popping and swelling. Radiohumeral synovial plica syndrome (RHSPS) may be an isolated condition or it can be associated with other elbow abnormalities. The findings on physical examination and imaging diagnosis are multiple and variable. Nowadays, RHSPS are quite unknown and previous reports do not seem to agree, leading to misdiagnoses as epicondylitis and making this structure the main cause of some cases of "intractable lateral epicondylitis". The outcomes of surgical treatments are quite promising although more, higher quality research is needed. Taking this into account, this review is meant to be a starting point for new anatomical and clinical studies.

A temporary disc-like structure at the median atlanto-axial joint in human fetuses

During observations of mid-term and late-stage fetuses, we found a joint disk-like structure at the anterior component of the median atlanto-axial joint. At mid-term, the disk-like structure was thick (0.1–0.15 mm) relative to the sizes of bones surrounding the joint. However, it did not completely separate the joint cavity, and was absent in the inferior and/or central part of the cavity. This morphology was similar to the so-called fibroadipose meniscoid of the lumbar zygapophysial joint that is usually seen in adults. In mid-term fetuses, there was evidence suggesting that a mesenchymal tissue plate was separated from a roof of the joint cavity. In late-stage fetuses, the thickness (less than 0.15 mm) was usually the same as, or less than that at mid-term, and the disk-like structure was often flexed, folded and fragmented. Therefore, in contrast to the zygapophysial meniscoid as a result of aging, the present disk-like structure was most likely a temporary product during the cavitation process. It seemed to be degenerated in late-stage fetuses and possibly also in newborns. Anomalies at the craniocervical junction such as Chiari malformations might accompany this disk-like structure at the median atlanto-axial joint even in childhood.

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.

Ultrasonographic Differentiation of Lateral Elbow Pain

Lateral elbow pain is often attributed to degenerative or posttraumatic impairment of the common extensor tendon. Ultrasonography assesses the soft tissue structures of the lateral elbow, allowing the differentiation between various underlying processes, including angiofibroblastic degeneration, hyaline degeneration, and inflammation, and exclusion of other possible causes of pain such as posterior interosseous and lateral antebrachial nerve compression. Furthermore, the real-time imaging nature of ultrasonography enables the detection of impingement of the lateral synovial fold, degenerative changes in the elbow recess, and elbow posterolateral instability during dynamic maneuvers. Ultrasonography is widely accessible and well tolerated by patients, making it a perfect method for establishing an initial diagnosis and monitoring the healing process. This review describes the possible causes of lateral elbow pain and their ultrasonographic differentiation.

Incidence, location and classification of glenoid labrum meniscoid folds

INTRODUCTION

The purpose of the present study was to arthroscopically investigate the incidence and location of labral meniscoid folds of the shoulder joint, as well as to classify them into types and detect any possible correlation with gender, side and age of patients.

MATERIALS AND METHODS

The shoulder joint of 59 patients who underwent arthroscopic surgery for different reasons was examined for meniscoid folds. We classified all meniscoid folds into slim or thick and large or small. The location and area of labral folds were assessed according to o'clock position and were defined by the center of the fold.

RESULTS

The incidence of labral meniscoid folds in shoulder joint was 62.7 %. Meniscoid folds were more frequently found at 2-o'clock position in right shoulders and at 10-o'clock position in left shoulders. Most of them were located in anterior and superior rim of labrum. Statistically significant difference (p = 0.018) was only detected between location of meniscoid folds and gender. In male patients meniscoid folds were mostly located in a more anterior position than women, whose meniscoid folds were found more superiorly. Older patients presented a higher rate of meniscoid folds.

CONCLUSION

Meniscoid folds are quite common in shoulder joint. Labral meniscoid folds are located more often at an anterosuperior position of shoulder joints and their incidence tends to be higher in older patients, while in male ones they are located in a more anterior position in comparison to female patients where they are located more superiorly.

Cricothyroid Articulation in Elderly Japanese With Special Reference to Morphology of the Synovial and Capsular Tissues

OBJECTIVE

The present study aimed to clarify individual variations in the cricothyroid joint (CT joint).

METHODS

Using 30 specimens of the CT joint obtained from elderly donated cadavers, we examined the composite fibers of the capsular ligament as well as the morphology of the synovial tissue.

RESULTS

The capsular ligament consistently contained abundant thick elastic fiber bundles on the anterior side of the joint (anterior band) and an elastic fiber-made mesh on the posterior side (posterior mesh). The synovial membrane, lined by synovial macrophages, was usually restricted to the recesses in the medial or inferior end of the joint cavity. Without the synovial lining, elastic fibers of the capsular ligament were subsequently detached, dispersed, and exposed to the joint cavity. We also observed a folded and thickened synovial membrane and a hypertrophic protrusion of the capsular ligament. In six specimens, the joint cavity was obliterated by debris of synovial folds and elastic fiber-rich tissues continuous with the usual capsular ligament. Notably, with the exception of two specimens, we did not find lymphocyte infiltration in the degenerative synovial tissue.

DISCUSSION

We considered the CT joint degeneration to be a specific, silent form of osteoarthritis from the absence of lymphocyte infiltration. For high-pitched phonation, the elderly CT joint 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. Conversely, however, high-pitched phonation may accelerate obliteration of the joint.

Anatomic relations between the lateral collateral ligament and the radial head: implications for arthroscopic resection of the synovial fold of the elbow

PURPOSE

The purpose of this study was to determine the anatomic relationship between the radial head and the lateral collateral ligament (LCL) and when the LCL would be at risk of iatrogenic injury during arthroscopic resection of the synovial fold.

METHODS

Thirty-four formalin-fixed upper extremities were dissected. A projection of the LCL onto the radial head was marked with a needle. The percentage of the posterior border of the radial head overlaid by the LCL was digitally measured. A portion of the projection of the LCL was statistically correlated with the overall diameter of the radial head.

RESULTS

The overall diameter of the radial head was 21.2 mm ± 2.3. The proportionate projection of the medial border of the LCL onto the radial head was 5.3 ± 1.6 mm on average. The lateral 25 % of the radial head was overlaid by the LCL with a maximum value of 40 % on average. The inter- and intraobserver reliability showed very good accordance with the digital measurements (r > 0.8).

CONCLUSION

Care must be taken when performing a resection in the lateral 40 % of the radial head, whereas resection in the medial 60 % of the radial head appears to be safe. The LCL is an important stabiliser of the elbow joint, a lesion of which by undeliberate arthroscopic dissection may lead to joint instability. Iatrogenic injury to the LCL presumably can be prevented when respecting the given data.

LEVEL OF EVIDENCE

Experimental study.

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.

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.

Joint capsule attachment to the extensor carpi radialis brevis origin: an anatomical study with possible implications regarding the etiology of lateral epicondylitis

PURPOSE

To identify the unique anatomical characteristic of the extensor carpi radialis brevis (ECRB) origin and points of differentiation from other extensors and to clarify the specific relationship of the ECRB to the underlying structures.

METHODS

We studied the origin of each extensor macroscopically for its muscular and tendinous parts; to identify the relationship between the ECRB origin and the deeper structures, we also examined the attachment of the joint capsule under the ECRB origin.

RESULTS

The ECRB simply originated as a tendon without any muscle, whereas other extensors originated as a mixture of tendon and muscle. At the anterior part of the ECRB origin, the thin attachment of the joint capsule (average width, 3.3 mm) lay deep to the ECRB and was distinct. However, at the posterodistal portion, the joint capsule, annular ligament, and supinator were intermingled and originated as a single wide sheet from the humerus (average width, 10.7 mm).

CONCLUSIONS

The anterior part of the ECRB origin was delicate, because the ECRB origin was purely tendinous, and the attachment of the articular capsule was thin compared with that of the posterodistal attachment. This thin attachment could be an initial factor leading to the development of lateral epicondylitis.

CLINICAL RELEVANCE

The results of the current study may enhance magnetic resonance imaging understanding and may help clarify the etiology of the lateral epicondylitis.

Articular cartilage changes in maturing athletes: new targets for joint rejuvenation

Context:

Articular cartilage has a unique functional architecture capable of providing a lifetime of pain-free joint motion. This tissue, however, undergoes substantial age-related physiologic, mechanical, biochemical, and functional changes that reduce its ability to overcome the effects of mechanical stress and injury. Many factors affect joint function in the maturing athlete—from chondrocyte survival and metabolism to structural composition and genetic/epigenetic factors governing cartilage and synovium. An evaluation of age-related changes for joint homeostasis and risk for osteoarthritis is important to the development of new strategies to rejuvenate aging joints.

Objective:

This review summarizes the current literature on the biochemical, cellular, and physiologic changes occurring in aging articular cartilage.

Data Sources:

PubMed (1969-2013) and published books in sports health, cartilage biology, and aging.

Study Selection:

Keywords included aging, athlete, articular cartilage, epigenetics, and functional performance with age.

Study Design:

Systematic review.

Level of Evidence:

Level 3.

Data Extraction:

To be included, research questions addressed the effect of age-related changes on performance, articular cartilage biology, molecular mechanism, and morphology.

Results:

The mature athlete faces challenges in maintaining cartilage health and joint function due to age-related changes to articular cartilage biology, morphology, and physiology. These changes include chondrocyte loss and a decline in metabolic response, alterations to matrix and synovial tissue composition, and dysregulation of reparative responses.

Conclusion:

Although physical decline has been regarded as a normal part of aging, many individuals maintain overall fitness and enjoy targeted improvement to their athletic capacity throughout life. Healthy articular cartilage and joints are needed to maintain athletic performance and general activities. Genetic and potentially reversible epigenetic factors influence cartilage physiology and its response to mechanical and injurious stimuli. Improved understandings of the physical and molecular changes to articular cartilage with aging are important to develop successful strategies for joint rejuvenation.

Elbow MR imaging findings in patients with synovial fringe syndrome

OBJECTIVE

To describe imaging findings in patients with synovial fringe (SF) syndrome of the elbow and to compare with a control population.

MATERIALS AND METHODS

Nine patients (5 men, 4 women) whose mean age was 35.7 years were diagnosed with SF syndrome and had undergone preoperative elbow MRI. The radiohumeral (RH) plica was assessed for thickness, cross-sectional area, coverage of one third or more of the radial head, blunting of the free edge, and T2 signal intensity abnormality. Other abnormalities of the RH joint were also assessed, including adjacent articular cartilage defects, subcortical bone marrow signal abnormality in the capitellum, and synovitis. Results were compared with 15 control patients who were asymptomatic laterally and posteriorly.

RESULTS

Mean thickness and cross-sectional area of the RH plica were 1.8 mm and 19.4 mm(2) respectively in controls, compared with 2.5 mm and 21.9 mm(2) respectively in symptomatic patients. No statistically significant differences in the distribution of the mean thickness or cross-sectional area of the RH plica were found between the two groups. However, 67% of SF syndrome patients had a RH plica thickness greater than 2.6 mm compared with only 13% of controls (p = 0.021). Other abnormalities of the RH plica occurred more frequently in patients with SF syndrome compared with controls, but were not statistically significant.

CONCLUSION

In patients presenting with posterolateral pain or mechanical symptoms in the elbow, RH plica thickness greater than 2.6 mm on elbow MRI examinations may help identify patients with SF syndrome.

Synovial folds - a pain in the neck?

The synovial folds of the cervical spine are regarded as a potential source of neck pain and headache, especially following whiplash injury. Damage to the synovial folds following motor vehicle trauma has been well documented in post-mortem studies. However, methods of identifying injury to the synovial folds in the survivors of motor vehicle trauma have proven elusive to date. Recently, it has been made possible to image the synovial folds in vivo using magnetic resonance imaging. This now makes it feasible to investigate the potential involvement of synovial folds in the generation of neck pain and headache and its relief using spinal manipulation. This paper reviews critically the morphology of the synovial folds of the cervical spine that underpins the hypotheses proposed to explain their functional and clinical significance and a new system of naming and classifying the synovial folds is presented. Although there is some evidence to support the contribution of the synovial folds to neck pain, several theories have little or no support and require investigation and further evaluation. These findings have implications for understanding the anatomical basis of neck pain and headache and the rationale for the use of spinal manipulation in their management.

Arthroscopic, macroscopic, and microscopic anatomy of the synovial fold of the elbow joint in correlation with the common extensor origin

PURPOSE

The objective of our study was to clarify the arthroscopic, macroscopic, and microscopic anatomy of the radiocapitellar synovial fold of the elbow joint in correlation with the common extensor origin.

METHODS

We performed arthroscopy in 14 fresh-frozen cadaveric elbows and found the synovial fold covering the radial head or interposing in the radiocapitellar joint in 6. The fold was tagged with loop suture under arthroscopy to identify its exact location in gross anatomy. The radiocapitellar joint capsule was then resected without disturbing the continuity of the common extensor and lateral epicondyle. Macroscopic and histologic evaluation was performed for the lateral elbow capsular complex.

RESULTS

The synovial fold was found to be a triangular-shaped thickening of the capsule located on the proximal edge of the annular ligament. The mean distance between the lateral epicondyle and the base of the fold at the anterior edge, middle part, and posterior edge was 23 mm, 8 mm, and 13 mm, respectively. This structure was distinct from the annular ligament but was continuous with the radiocapitellar joint capsule. The joint capsule and the common extensor tendon blended with each other imperceptibly and formed a single enthesis at the lateral epicondyle.

CONCLUSIONS

The synovial fold identified by arthroscopy is a physiologic capsular tissue located on the proximal edge of the annular ligament. It is distinct from the annular ligament but has a close correlation with the common extensor tendon enthesis at the lateral epicondyle.

CLINICAL RELEVANCE

The synovial fold belongs to the lateral epicondyle enthesis, which is a composite of the common extensor tendon, undersurface capsule, and bone. Therefore, lateral epicondylitis with degenerative lesions in the area of the common extensor origin may involve the synovial fold and induce hypertrophic changes.

Intra-articular inclusions of the elbow joint complex

An abundant clinical literature implicates intra-articular inclusions in various pathological conditions of the elbow, but the anatomical literature offers piecemeal descriptions of these structures. The aim of this study was to determine the prevalence, disposition, and gross morphology of intra-articular inclusions of the entire elbow joint complex. Twenty-eight elbow joints from 17 adult embalmed cadavera were studied by macrodissection. Three types of inclusions were identified. Fat pads and fibroadipose meniscoids were found in all joints while capsular rims occurred in 50% of radiohumeral and humeroulnar joints. Fat pads were located opposite the olecranon, coronoid, and radial fossae. Fibroadipose meniscoids were found in the nonarticular waists of the trochlear notch and protruded into the posterolateral aspect of the radiohumeral joint. Fibroadipose meniscoids and fat pads are characteristic structures of the elbow joint complex. Fat pads appear to act as deformable space fillers, while the radio-humeral fibroadipose meniscoid appears to protect articular cartilage exposed during normal movement. Arguments are raised whether these structures may act as the nidus for arthrofibrosis and that the radiohumeral meniscoid may be involved in lateral epicondylalgia.

Ultrasonographic examination of the synovial fold of the radiohumeral joint

This report describes the anatomy of the synovial fold of the radiohumeral joint and assesses its visibility by ultrasonography. Forty-nine fresh cadaver radiohumeral joints were examined by ultrasonography before and after intraarticular saline injection and then dissected. Digital photos were taken before and after the joint capsule was excised. The relative coverage of the radial head by the fold was calculated. Synovial folds were observed in all specimens. Forty-three had anterior and posterior lobes. The synovial fold covered an average of 28% of the radiocapitellar joint surface of the radial head. The sensitivity of the ultrasonography was 81%, 46%, and 85% from the anterior, lateral, and posterior aspects of the radiohumeral joint, respectively. Intraarticular saline injection improved the sensitivity to 96%, 67%, and 94%, respectively. The synovial fold is a consistent anatomic structure, and ultrasonography can be a useful preoperative diagnostic tool.

Usefulness of MRI for diagnosis of painful snapping elbow

Painful snapping of the elbows is rare. We report on a 12-year-old boy with a painful snap in both elbows. High-resolution magnetic resonance imaging of the elbow using microscopy coils detected a synovial fold interposed in each humeroradial joint and was very helpful in establishing the cause of symptoms. Resection of the synovial folds was performed with subsequent relief of symptoms.

Bilateral painful snapping elbows triggered by daily dumbbell exercises: a case report

We treated a 64-year-old female with bilateral painful snapping elbows due to synovial folds. Resection of the bilateral synovial folds resulted in relief from pain and snapping, and resulted in patient satisfaction. Daily dumbbell exercises of the bilateral elbows starting at an elderly age may have led to the bilateral snapping. Painful snapping elbow is a relatively rare condition, which usually occurs in a unilateral elbow of a younger patient. To our knowledge, bilateral painful snapping elbows triggered by daily dumbbell exercises in older patients have not been previously reported.

The posterolateral plica: a cause of refractory lateral elbow pain

Lateral epicondylitis is one of the most common upper extremity pain syndromes. We report the results of patients in whom conservative treatment was unsuccessful and who were finally treated arthroscopically for symptomatic plicae. Ten patients (mean age, 40 years [range, 18-60 years]) who were misdiagnosed as having lateral epicondylitis were included in this study. Examination revealed the site of maximal tenderness to be posterior to the lateral epicondyle and centered at the posterior radiocapitellar joint. Preoperatively, all patients received conservative treatment (physical therapy or corticosteroid injections [or both]). The mean follow-up was 25 months (range, 6-68 months). The mean score on the Disabilities of the Arm, Shoulder and Hand questionnaire was 9 (range, 0-37). Preoperatively, 7 patients had full elbow range of motion; however, in 3 patients, there was a loss of extension at the elbow ranging from 7 degrees to 20 degrees preoperatively. The range of elbow motion was full in all patients postoperatively. No patient demonstrated posterolateral pain after the operation. Synovial plicae of the elbow may be the cause of lateral elbow pain in patients with vague clinical symptoms. Arthroscopic management may provide a successful treatment option for such patients.

A meniscus causing painful snapping of the elbow joint: MR imaging with arthroscopic and histologic correlation

Snapping of the elbow joint can cause pain. We report a case of painful snapping elbow produced by an interposed meniscus in the radiohumeral joint in a 20-year-old man. The MR arthrogram demonstrated a meniscus-like tissue interposed between the radial head and humeral capitellum. The MR-arthrographic findings were well correlated with surgical findings. The location and appearance of the meniscus-like tissue was similar to that of meniscus in the knee joint. Histologic findings of the excised meniscus-like tissue showed a typical presentation of fibrocartilage. A meniscus may exist in the elbow joint and can be a rare cause of painful snapping elbow. MR arthrography is helpful for identifying the snapping tissue in the elbow joint.

Morphometry of the lumbar zygapophyseal facet capsule and cartilage with special reference to degenerative osteoarthritic changes: an anatomical study using fresh cadavers of elderly Japanese and Korean subjects

Morphometric data were obtained from fresh cadaver dissections, and observations of degenerative changes in the joint cartilage (DCs) were analyzed to determine whether the morphometric parameters of the lumbar zygapophyseal joint capsule varied according to the presence and severity of DCs. There have been no previous morphometric studies of the facet capsule that describe age-related DCs. Using 23 fresh osteoligamentous lumbar spines from donated cadavers, we performed morphometric investigations of the surface areas of the joints and their capsules and measured the capsular thickness. We hypothesized that the ratio of the inner capsular area to the joint surface area for each facet (the capsule/facet index) could serve as an index showing a functional aspect of a large or small capsule. Our results showed that the joint surface area increased significantly with increasing severity of DCs, according to Grogan's classification. Facets with advanced DCs tended to have a small inner capsular surface. The capsule/facet index generally correlated positively with capsular thickness, especially the dorsal portion; however, this was not true for the ventral portion. The index also correlated negatively with DC progression. Thus, lumbar facet DCs were strongly linked to reconstructive alterations in capsular size, thickness, and looseness. The occurrence and progression of DCs narrowed the joint capsule, especially the dorsal portion, and this seemed to decrease the potential looseness of the joint. Conversely, these capsular alterations seemed to accelerate DC progression. A negative adaptation cycle seemed to occur.

Snapping annular ligament of the elbow joint in the throwing arms of young brothers

We examined young brothers with symptomatic snapping elbow in the throwing arm. Arthroscopic examination confirmed the mechanism of snapping, in which loose and protruded annular ligament-like tissue covered the volar half of the radial head in elbow extension and uncovered the radial head in deep elbow flexion. Arthroscopic resection of the annular ligament-like tissue was performed in one brother. Histologic examination of the removed tissue showed degenerated ligament tissue. Excision of loose annular ligament abolished snapping. Contralateral elbows of the brothers also showed similar asymptomatic snapping. Researchers suggest that a hereditary factor contributing to loose annular ligament and repetitive microtrauma from throwing is the cause of symptoms.

Does the meniscus exist in the elbow joint in children?

The authors report a case of meniscus at the elbow joint in a 15-month-old infant causing a limitation of elbow extension. Histological examination demonstrated that this tissue was not a synovial fold or a chondroid metaplasia of the synovial fold. As a meniscus does not appear at any stage of the embryological evolution of the elbow joint, it has been concluded that the presence of the meniscus can be considered as an abnormal condition.

Topographic anatomy of the male perineal structures with special reference to perineal approaches for radical prostatectomy

AIM

Although perineal approaches for radical prostatectomy have recently gained renewed attention as excellent methods for minimally invasive surgery, the most commonly used techniques, Belt's and Young's approaches, have inadequacies regarding the topographical relationship between the rectourethral and levator ani muscles.

METHODS

Using macroscopic observations of sagittal slices of 27 male pelvises and smooth muscle immunohistochemical staining of semiserial sections of another eight pelvises, we investigated the topographical anatomy of the perineal structures and their interindividual variations in elderly Japanese men.

RESULTS

The inferomedial edge of the levator ani was located 5-15 mm lateral to the midsagittal plane in an area between the urethra and the rectum. The rectourethral smooth muscle had a superoinferior thickness of 5-10 mm and occupied a space between the right and left levator slings. The levator was adjacent to, or continuous with, the striated anal sphincters. A thick connective tissue septum, composed of smooth muscle, was evident between the rectal smooth muscle and the anal sphincter-levator ani complex.

CONCLUSION

Because the connective tissue septum guides the surgeon's finger upwards towards the rectoprostatic space, Belt's approach appears relatively easy; however, rectal injury can sometimes occur if the surgeon loses this guidance. In contrast, if the levator edge is identified as the first step in Young's approach, the rectourethral muscle can be precisely divided, leaving a 3-5-mm margin from the rectum and sphincter-levator complex. Clinical investigations are now required to modify Young's approach based on the present results.

The lateral collateral ligament complex and related muscles act as a dynamic stabilizer as well as a static supporting structure at the elbow joint: an anatomical and experimental study

Among 71 osteoligamentous elbow joint specimens from Japanese subjects, 66% of the lateral ulnar collateral ligaments (LUCLs) were in an incomplete form, such as a fibrous intermuscular septum lying between the anconeus, supinator and extensors, and terminated on the annular ligament. The 'typical' complete ligament, extending from the lateral epicondyle and over the radial collateral ligament (RCL) to the crista spinatoris, appeared in only 20% of the elbows examined. This observation suggests that, in Japanese subjects, the LUCL is not usually a simple ligamentous static stabilizer, but acts as a dynamic stabilizer, together with its related muscles. In addition, when the elbow was flexed by more than 90 degrees, the distance between the lateral epicondyle and the radial head became almost 1.5 mm larger than the distance from the epicondyle to the annular ligament. We therefore consider that, in the overflexed position, the radial head moves slightly distal while the length of the RCL remains almost constant. This morphometrical observation suggests that the annular ligament needs to be supported by the LUCL-muscle complex from the distal side, as well as by the RCL from the proximal side. This extended definition of the lateral collateral ligament complex and its associated muscular function is discussed.

Morphometrical study of the joint surface and capsule of the lumbar zygapophysial joint with special reference to their laterality

Using 26 osteoligamentous lumbar vertebral columns (260 facets), we morphometrically investigated the cartilagenous joint surface, inner capsular surface and capsular thickness. We also examined whether the subcapsular pocket was present and, if present, how far it extended along the joint margin. The proportion of the inner capsular area in the total joint surface area in a facet (the capsular-joint surface ratio) was hypothesized to correspond to the potential looseness (or tightness) of the facet. The absolute data themselves seemed to be useful for better understanding of the joint morphology. However, further evaluations of the differences between segments, left/right differences, individual segmental fluctuation patterns and correlations between parameters provided a novel classification of specimens according to the hypothetical progress of joint degeneration. Criteria for the classification existed in 1) the laterality in parameters defined as more than 100% larger or smaller than the contralateral facet and 2) the drastic segmental difference in parameters over 50% larger or smaller than the adjacent segment. Consequently, three types were identified: 1) outside of the criteria in both area and thickness (-/- type, 9 of 26); 2) the criteria did not fit the area parameters but did fit the thickness parameters (-/+ type, 8); the criteria were filled in both categories of parameters (+/+ type, 9). Notably, in the +/+ types, the capsular thickness and capsular-joint surface ratio correlated significantly (p < 0.01), i.e., the hypothetical loose joint had a thick capsule. We speculated that early joint degeneration starts from the -/- type and advances via the -/+ type to the +/+ type. Considerating these results, we recommended using MR imaging for detailed identification of laterality in the capsular thickness for low-back pain patients to discriminate candidates for future severe degenerative changes of the articular cartilage in the lumbar spine.