Arthroscopic subscapularis repair using the subscapularis interlocking (SICK)-stitch technique leads to restoration of clinical function with low complication and revision rates.

Background: The purpose of this study is to determine the mid-term outcome after arthroscopic subscapularis tendon (SCP) reconstruction using the subscapularis interlocking (SICK)-stitch technique. The hypotheses are that arthroscopically repaired SCP lesions using the SICK-stitch show a good restoration of shoulder function with low complication and failure rates. Methods: This is a retrospective monocentric study of n = 199 patients (n = 106 female) with arthroscopically treated SCP tears with the interlocking (SICK) stitch technique from July 2013 to October 2018. Inclusion criteria: minimum follow-up of 2 years. Exclusion criteria: irreparable and massive cuff tears, osteoarthritis, and fractures. The postoperative assessment consisted of the range of motion, constant score, simple shoulder test, simple shoulder value, disability of the shoulder and arm score, short form 12, and patient satisfaction. Results: Mean age was 61 years (25-83); n = 4 (2%) patients were lost to follow-up with mean follow-up time of 63.6 months (36-96). Additional supraspinatus tendon lesions (n = 147) were repaired in n = 101 cases. SCP grading (n = 69) (35% traumatic) (Fox/Romeo): n = 113 grade II, n = 71 grade III, n = 11 grade IV. A positive preoperative lift-off test (n = 132, 68%) was corrected in n = 124 (94%) of cases. Ninety seven percent of patients would undergo surgery again with a mean satisfaction score of 14.4/15. Results at final follow-up (data: mean pre; post; P value): lexion (130; 166; .001), abduction (123;159; .001), external rotation (35;82; .001), internal rotation (52; 68; .07), constant score (50; 82; .001), disability of the shoulder and arm score (40; 19; .001), simple shoulder test (5; 10; .001), and simple shoulder value (44; 83; .001) significantly improved. The mean physical health scale short form 12 was 46 (24-63) and 51 (15-66) for mental health. Age, body mass index, SCP-grading, and supraspinatus tendon repair did not significantly affect any outcome parameter. Three (1.5%) patients underwent revision surgery, of which 1 (0.5%) had an infection. Conclusion: Two years after arthroscopic SCP repair using the SICK-stitch technique, we observed excellent restoration of clinical function with low complication and revision rates. The SICK-stitch technique thus represents a good and reliable therapeutic option for the arthroscopic repair of SCP lesions.

Midterm outcomes of autologous bridging of rotator cuff tears with an autologous tendon patch (TEAR patch).

BACKGROUND: Large and massive rotator cuff tears and tears after failed surgical repair are a challenging clinical problem with different treatment options. The purpose of the study was to evaluate the midterm outcomes after rotator cuff repair (RCR) with autologous hamstring tendon graft bridging (tissue-enhanced autologous rotator cuff repair [TEAR] patch) with the hypothesis that outcomes would be reasonable and complication rates would be low. METHODS: This is a retrospective case series study of patients who underwent open RCR using a TEAR patch from June 2015 to March 2019. The exclusion criteria included evidence of cuff tear arthropathy, advanced fatty infiltration, moderate-to-severe arthropathy, and workers compensation board or litigation involved. Clinical outcome measures were Constant score; Disabilities of the Arm, Shoulder and Hand score; Simple Shoulder Test; Subjective Shoulder Value; range of motion (ROM); and manual muscle test for forward elevation, abduction, external and internal rotation, patient satisfaction, and willingness to perform the operation again. Radiographic outcome measures were magnetic resonance imaging, ultrasound, and radiographs: graft integrity and acromiohumeral distance (AHD). RESULTS: A total of 44 patients were followed (89%) for ≥2 years (45 shoulders, mean age 60.3 years [48-76 years], mean follow-up 4.3 years [2-6 years]). All clinical outcome measures (Constant score, Disabilities of the Arm, Shoulder and Hand score, Simple Shoulder Test, Subjective Shoulder Value, ROM, and manual muscle test) demonstrated significant improvement except active external and internal rotation. At 2 years of follow-up, the mean patient satisfaction was high (12.2 of 15 points), and 33 of 38 patients (73.3%) would perform the operation again. A perfect graft integration was observed in 30 (66.7%), a small gap in 7 (15.6%), a retear in 3 (7%), and a complete failure of the tendon patch in 5 (11%) patients. Graft integrity was strongly correlated with the postoperative AHD (r = 0.599, P = .001) and the gain in AHD (r = 0.599, P = .001) but not with ROM or patient-reported outcome measures or patient satisfaction. Four patients required revision surgeries (3 due to deep infection and 1 for poor function and pain). CONCLUSIONS: Midterm clinical and radiographic outcomes after RCR with graft bridging using a TEAR patch were reasonable. The procedure resulted in improved shoulder function and a high level of patient satisfaction. The revision rate is acceptable in view of the specific patient group and treatment alternatives. The described technique of the TEAR patch can be a valuable alternative to existing methods and a new autograft source for rotator cuff surgeries that need bridging of a tendon defect.

Arthroscopic Posterior HAGL Repair Using a Direct Transaxillary Portal.

Humeral avulsion of the glenohumeral ligament (HAGL lesion) is a challenging problem in surgery for shoulder instability. Open and arthroscopic approaches and techniques have been described to address this issue. Especially posterior HAGL lesions increase the surgical complexity, as open anterior approaches provide limited visibility and access for successful repair. This article describes an alternative technique using an arthroscopic transaxillary approach to deploy the suture anchor with a perpendicular angle to the humeral bone, thus, improving the ability to perfectly position the anchor at the anatomic insertion of the inferior humeral ligament.

[The shoulder and elbow register of the DVSE-trend monitoring or early warning system? : A literature-based analysis]. / Das Schulter- und Ellenbogenregister der DVSE ­ Trendbeobachtung oder Frühwarnsystem? : Eine literaturbasierte Analyse.

The endoprosthesis register (SEPR) of the D­A-CH Association for Shoulder and Elbow Surgery e. V. (DVSE) collects data on the implantation of shoulder and elbow endoprostheses. The question arises as to whether the data is only used to monitor trends in arthroplasty, or whether it can also be used as an early warning system for risks and possible complications. The existing literature on the SEPR was analyzed and compared with other national endoprosthesis registries. The SEPR of the DVSE enables the collection and analysis of epidemiological data on primary implantation, follow-up and revision in shoulder and elbow endoprosthetics. It is an instrument of quality control and contributes to ensuring the greatest possible patient safety. It is used for the early detection of risks and potential requirements associated with shoulder and elbow arthroplasty.

[Conversion of anatomic to reverse shoulder arthroplasty : Does it make sense?] / Konversion von anatomischer auf inverse Prothese : Macht das Sinn?

We can observe increasing numbers for the implantation of shoulder endoprostheses in developed industrial countries. This is accompanied by a certain number of revision surgeries. The conversion to reverse arthroplasty systems is by far the most common revision procedure. Depending on the primary implant and the individual situation, the surgical effort and consumption of resources can be substantial. Particularly favorable revision scenarios exist in the conversion of stemless primary implants that are part of a platform system and allow a partial exchange and easy conversion from anatomical to reverse implants.

Morphology of the acromioclavicular-joint score (MAC).

INTRODUCTION: To date there is no generally accepted specific definition or classification of acromioclavicular (AC) joint osteoarthritis. The aim of this study is to analyze morphological parameters using magnetic resonance imaging (MRI) and to develop a scoring system as a basis for decision making to perform an AC-joint resection. MATERIALS AND METHODS: In a retrospective-monocentric matched pair study, healthy and affected subjects were investigated using T2 MRI scans in the transverse plane. There were two groups, group 1 (n = 151) included healthy asymptomatic adults with no history of trauma. In group 2, we included n = 99 patients with symptomatic AC joints, who underwent arthroscopic AC-joint resection. The central and posterior joint space width and the AC angle were measured. Morphological changes such as cartilage degeneration, cysts and bone edema were noted. Malalignment of the joint was defined as: posterior joint space width < 2 mm in conjunction with an AC angle > 12°. A scoring system consisting of the measured morphologic factors was developed. RESULTS: Symptomatic and asymptomatic patients showed significant differences in all measured items. We observed a significant difference in the MAC score for symptomatic and asymptomatic patients (mean 10.4 vs. 20.6, p = 0.0001). The ROC (receiver operator characteristic) analysis showed an excellent AUC of 0.899 (p = 0.001). The sensitivity of the MAC score was 0.81 and the specificity 0.86. The MAC score shows a significant moderate correlation with age (r = 0.358; p = 0.001). The correlation of age and the development of symptoms was only weak (r = 0.22, p = 0.001). Symptomatic patients showed significantly more frequent malalignment compared to asymptomatic patients (p = 0.001), but the positive predictive value that a patient with malalignment is also symptomatic is only 55%. CONCLUSION: Patients with symptomatic AC joints showed a typical pattern of morphological changes on axial MRI scans with early posterior contact of the joint surfaces, reduction of joint space and malalignment as the basis for the development of a scoring system. The MAC score shows excellent test characteristics, and therefore, proved to be both an appropriate guidance for clinical practice as well as an excellent tool for comparative studies and is superior to the assessment of malalignment alone. LEVEL OF EVIDENCE: Level IV, retrospective diagnostic study.

Anterolateral Acromioplasty Does Not Change the Critical Shoulder Angle and Acromion Index in a Clinically Relevant Amount.

PURPOSE: Assessment on whether radiographic parameters of the acromion measured in radiographs change significantly after anterolateral acromioplasty. METHODS: This retrospective study included patients that underwent an arthroscopic anterolateral acromioplasty between January 2014 and September 2020. n = 435 subjects with high-quality preoperative and postoperative radiographs according to Suter-Henninger criteria were included in the final assessment. All measurements were independently performed by the first and second author in a blinded fashion using dicomPACS software: acromion index (AI), critical shoulder angle (CSA), lateral acromial angle (LAA), beta angle, acromio-humeral distance (AHD), Aoki angle, frontal supraspinatus outlet angle (FSOW), and acromion type, according to Bigliani. SPSS software was used for statistical analysis. RESULTS: The beta angle and the CSA did not significantly change after operation (alpha power 0.32 and 0.11, respectively). In a subgroup analysis of patients with a pathological CSA >35° (n = 194), the CSA changed from 38.62 (range: 35.08-47.52, SD 2.83) to 38.04 (range: 29.18-48.12, SD 3.77) postoperatively (P = .028) (Fig 8). All other parameters changed significantly after operation (AI, AHD, FSOW, and Aoki; P = .001, LAA; P = .039) (Fig. 9). The interobserver and intraobserver reliability was good to excellent in the majority of measured values. Mean patient age was 59.2 years (range: 18.1-87.1; SD 11.3), mean height was 1.73 meters (range: 1,50-1.98, SD 0.09), mean weight was 80.2 kg (range: 37.0-133.0, SD 16.68), and mean body mass index was 26.6 (range: 0.0-46.1, SD 4.73). CONCLUSION: Anterolateral acromioplasty producing a flat acromion undersurface did not result in a significant change of the CSA in the study population. Pathological preoperative CSA values of >35° were significantly reduced but not to normal values, but only by a small amount that puts the clinical relevance into question. LEVEL OF EVIDENCE: IV, diagnostic study, case series.

Dexamethasone Does not Compensate for Local Anesthetic Cytotoxic Effects on Tenocytes: Morphine or Morphine Plus Dexamethasone May Be a Safe Alternative.

Purpose: The purposes of this in vitro study were to investigate whether the addition of dexamethasone can compensate for any cytotoxic effects of the amide-type local anesthetics (LA) bupivacaine and ropivacaine and whether morphine and morphine-6-glucuronide (M6G) may be a safe alternative for peritendinous application. Methods: Biopsies of human biceps tendons (n = 6) were dissected and cultivated. Cells were characterized by the expression for tenocyte markers, collagen I, biglycan, tenascin C, scleraxis, and RUNX via reverse transcriptase-polymerase chain reaction and immunohistochemistry. Tenocytes were incubated with bupivacaine, ropivacaine, morphine, M6G, or a saline control with and without addition of dexamethasone for 15, 60, or 240 min. Cell viability was determined by quantifying the presence of adenosine-triphosphate. Results: Significant time-dependent cytotoxic effects were observed for LA after all exposure times. After 15, 60, and 240 minutes, cell viability decreased to 81.1%, 49.4% and 0% (P < .001) for bupivacaine and to 81.4%, 69.6%, and 9.3% (P < .001) for ropivacaine compared to saline control. Dexamethasone did not compensate for these cytotoxic effects. Cell viability was not affected after 15, 60-min exposures to morphine and M6G but decreased significantly (P < .001) after 240 minutes compared to saline control. However, in combination with dexamethasone, tenocyte viability was significantly increased at all times for morphine (P < .01) and at 15 and 60 minutes for M6G (P < .01). Conclusions: The results showed that amide-type LA have a time-dependent cytotoxic effect on human tenocytes in vitro, which could not be compensated for by dexamethasone, whereas morphine and M6G had no cytotoxic effects on tenocytes after 15 and 60 minutes. The addition of dexamethasone to morphine and M6G had a positive effect on viability, which increased significantly compared to the opioids. Clinical Relevance: It is known that amide-type local anesthetics used for local joint analgesia have chondrotoxic side-effects. The combined application of morphine and dexamethasone may be a safe alternative.

Editorial Commentary: Elbow Arthroscopy in the Pediatric Patient-Small Lesions in a Small Joint but With a Big Impact.

Elbow arthroscopy has evolved to be a powerful tool for the treatment of a broad spectrum of pathologies over the past almost 40 years. The small joint with a complex arthroscopic anatomy demands special training and exceptional skills from the orthopaedic surgeon. On the basis of this fact and in light of the close proximity of the neurovascular structures, complication rates are somewhat higher compared with other large joints such as the knee and the shoulder. Nevertheless, elbow arthroscopy has also found its way into the treatment of joint pathologies in pediatric patients. The spectrum of pathologies differs from that in the adult population, with fewer degenerative changes and many growth-related issues such as osteochondral lesions (osteochondritis dissecans) of the capitellum. Generally speaking, clinical outcomes, return to sports, and patient satisfaction are excellent and complication rates are low. The latter remains a target for further improvement in light of the many years those pediatric elbow joints have ahead.

Analysis of revision shoulder arthroplasty in the German nationwide registry from 2014 to 2018.

BACKGROUND: The purpose of this study is to identify and analyze primary revision arthroplasties of the shoulder in the Germany Shoulder Arthroplasty Registry. The objective is to provide demographic and clinical data of the included cases and information about the revision surgery itself and to compare the findings to other registry studies and clinical studies. METHODS: All documented cases of primary revision arthroplasties of the Germany Shoulder Arthroplasty Registry in the time period 2014-2018 (n = 975) were included in the initial data analysis. Exclusion criteria were multiple revisions and data sets with a missing link of the revision arthroplasty to the data set of the primary implantation leaving n = 433 cases that were included. SPSS software (IBM SPSS Statistics for Windows, version 24.0; IBM Corp., Armonk, NY, USA) was used for statistical analyses. RESULTS: The age of patients with revised anatomic implants (66.3 years) was significantly lower than that of patients with reverse implants (77.1 years) (P = .001). Female patients with anatomic and fracture implants were significantly older than their male counterparts (70.1 vs. 60.5 years, P = .001; 74.3 vs. 62 years, P = .019) and showed a significantly higher rate of revision than their male counterparts (P = .001). The reason for revision was significantly different for anatomic and reverse implant systems (P = .001). Aseptic loosening of either the humeral or glenoid component was the most common reason for revision for anatomic implants, whereas unspecified reasons, dislocation, and loosening of the glenosphere were the most common reasons for reverse implants. The most common type of revision procedure for anatomic implants was conversion to a reverse system in about one third of the cases. Most of the revisions of reverse implants were not specified and almost equally distributed for revision at the humeral or the glenoid side. Anatomic implants showed significantly better Constant-Murley scores (26.1 points) than reverse implants (19.6 points) (P = .001) and significantly better function before revision for passive flexion (P = .002), passive abduction (P = .015), active external rotation (P = .002), and passive external rotation (P = .002). CONCLUSION: This study provides a well-documented basis to compare revision arthroplasties of the shoulder performed in Germany over the last decade as documented in the nationwide registry with other nationwide registries and with clinical studies. Especially, the detailed analysis of intraoperative and postoperative complications and the shoulder function at the time of revision offers new information in addition to the results of other registries.

Delta-Loop-Stitch: Three-Point Fixation for Combined Radial and Tangential Capsular Shift for the Treatment of Multidirectional Instability of the Shoulder and Hyperlaxity.

Multidirectional shoulder instability and hyperlaxity can be treated with arthroscopic shoulder stabilization and capsular shift. In these patients, the joint capsule often becomes the weak link in terms of pullout strength and cutting through of the used sutures, which can further be compromised by reduced quality of the capsular tissue. The described delta-loop-stitch combines a loop stitch through the capsule with a 3-point-fixation to the intact labrum thus distributing the load and reducing the risk of failure of the fixation. The suture knots are directed under the joint capsule away from the articulating surfaces to reduce the risk of iatrogenic lesions of the articular cartilage. The circumferential application of the delta-loop-stitch allows a sufficient capsular shift that combines a radial and tangential shift and reduction of the overall joint volume that can be adjusted to the patient's individual situation and the surgeon's preference.

Subscapularis Tendon Tears - Usefulness of Written MRI Reports for Guiding Patient Referral to Shoulder Specialists.

INTRODUCTION: Rotator cuff tears are one of the most common reasons for shoulder pain, and patients often present initially to general practitioners. However, subscapularis tears are especially difficult to diagnose and hence adequate therapy is often delayed. General practitioners or non-specialist orthopedic surgeons need reliable MRI findings to allow timely referral of patients to shoulder specialists. The purpose of this study was to determine the validity of the written MRI report of patients with arthroscopically proven subscapularis tendon tears. METHOD: In this retrospective study, 97 patients (mean age 62.4 ±â€Š10 years, 63 men) who underwent arthroscopic subscapularis repair between April 2013 and January 2015 by two experienced shoulder surgeons and who underwent a preoperative 1.5 T MRI study were included. All of these patients had high-field strength (i. e., ≥ 1.5 T) standard MRI scans performed within 4-164 (mean 57.4 ±â€Š38.4) days before their arthroscopic procedures. RESULTS AND CONCLUSION: Subscapularis tendon tears, verified by arthroscopy, were correctly identified in only 37 of 97 cases in the written report of the preoperative MRI. This resulted in an overall low sensitivity of 38.1 %. Correctly predicted lesions were as follows: Fox and Romeo I 29.4 % (5/17 patients), Fox and Romeo II 20 % (7/35 patients), Fox and Romeo III 46.7 % (14/30 patients) and Fox and Romeo IV 73.3 % (11/15 patients). In contrast, concurrent supraspinatus tendon tears were identified correctly in 88.2 % of patients (60/68 cases, sensitivity 88.2 %, specificity 96.5 %). Preoperative written radiology reports provided by a heterogeneous group of 39 presumably non-MSK-specialized radiologic centers do not reliably detect subscapularis tendon tears and are not sufficient for guiding patients to specialist centers. Compared to other rotator cuff injuries, this study shows difficulties in the correct diagnosis of subscapular tendon injuries. However, this is necessary to provide patients with timely therapy. It can be assumed that MRI review by musculoskeletal-specialized radiologists would more often than not lead to the correct diagnosis. KEY POINTS: · Subscapularis tendon ruptures are difficult to diagnose on standard shoulder MRI.. · Written MRI reports from non-musculoskeletal-specialized radiologists are not reliable, especially for smaller lesions.. · Reliable findings are required for referral allocation to shoulder specialists (specialized musculoskeletal radiologists).. CITATION FORMAT: · Lenz R, Kircher J, Schwalba K et al. Subscapularis Tendon Tears - Usefulness of Written MRI Reports for Guiding Patient Referral to Shoulder Specialists. Fortschr Röntgenstr 2021; 193: 797 - 803.

Reconstruction of a Central Full-Thickness Glenoid Defect Using Osteochondral Autograft Technique from the Ipsilateral Knee.

BACKGROUND: Osteochondral defects (OCDs) of the shoulder represent a typical clinical problem and are difficult to manage. OCDs of the upper extremity are less common than those of the lower extremity. The incidence is reported to be between 5-17% in which the humerus is affected more frequently than the glenoid. OCD is often accompanied with symptoms and may appear secondary to trauma, instability or prior operation. The problem of the lesions is the missing blood circulation which makes the healing impossible. The hazard of OCDs is the progression to osteoarthritis. In spite of the effectiveness of total shoulder arthroplasty it is not the first option for young and active patients. The therapy options of OCD depend on the size and localization of the defect. PURPOSE: The aim of this multimedia article is to reveal a therapy option for OCDs of the glenoid. METHODS: In this case we present the reconstruction of a central full-thickness osteochondral glenoid defect with an osteochondral autograft from the ipsilateral knee which was withdrawn using the OATS-Technique (Arthrex, Naples, Florida) to address the chondral as well as the osseous pathology. To the best of our knowledge there has been no such procedure performed and described so far. RESULTS: The procedure lead to proper restoration of the defect. CONCLUSION: The demonstrated technique can be used to perform the reconstruction of a full-thickness osteochondral glenoid defect.

Editorial Commentary: The Measurement of Knee Laxity: Instrumented Measurement and Stress Radiography for Anterior Cruciate Ligament Injuries.

The measurement of anterior knee laxity in anterior cruciate ligament injuries is an established method for both clinical practice and clinical studies in regard to anterior cruciate ligament surgery. Stress radiography was succeeded or paralleled by instrumented testing with the development of standardized devices starting in the 1980s. Because knee stability depends on the flexion angle test, conditions need to be comparable for both instrumented testing and stress radiography. The lack of a general consensus becomes even more evident for testing and measuring rotational instability. Knee laxity measurement in all dimensions, such as with robots in cadaver studies, has not found its general application in the clinical setting yet, but will be expected in the near future.

Thickness Distribution of Glenohumeral Joint Cartilage.

High-resolution 3-dimensional cartilage-specific magnetic resonance imaging (MRI) was performed at 3 T to test the following hypotheses: (1) there is a nonuniform cartilage thickness distribution both on the proximal humerus and on the glenoid surface and (2) the glenohumeral joint as a combined system is congruent with the level of the joint cartilage surface without substantial radial mismatch. Inclusion of 38 volunteers (19 females, mean age 24.34 ± 2.22 years; range 21-29 years) in a prospective study. Measurements of: cartilage thickness in 3 regions and 3 zones; radius of both circles (glenoid and humeral cartilage) for congruency calculation using 3-T MRI with 3-dimensional dual-echo steady-state sequence with water excitation. A homogenous mean cartilage thickness (1.2-1.5 mm) and slightly higher values for the glenoidal articulating surface radii both in the mid-paracoronar section (2.4 vs. 2.1 cm, P < 0.001) and in the mid-paraaxial section (2.4 vs. 2.1 cm, P < 0.001) compared with the humeral side were observed. The concept of a radial mismatch between the humeral head and the glenoid in healthy human subjects can be confirmed. This study provides normative data for the comparison of joint cartilage changes at the shoulder for future studies.

The influence of suprapectoral arthroscopic biceps tenodesis for isolated biceps lesions on elbow flexion force and clinical outcomes.

PURPOSE: To prospectively evaluate elbow flexion force, cosmetic and clinical outcome of all-arthroscopic suprapectoral biceps tenodesis for isolated biceps lesions. METHODS: Tenodesis was performed using a 6.25-mm absorbable interference screw for intraosseous fixation. Seventeen out of 24 patients (70.8 %, median age 49.0 ± 10.1 years; 10 = male) could be included for 24 months follow-up. Elbow flexion strength in 10° and 90° elbow flexion, the upward-directed force of the upper arm in the O'Brien position, objective evaluation of a Popeye-sign deformity and validated clinical scores (CMS, SST, ASES) were assessed preoperatively, 3, 6, 12 and 24 months postoperatively. RESULTS: Elbow flexion strength in 90° improved significantly from 12 months onwards (P = 0.001) without significant difference to the contralateral arm from 3 months postoperatively (n.s.). At 24 months, an average increase of 46.4 % (median 37.7 %) from preoperative could be seen. The dominant arm was affected in 70.6 %. All scores showed a significant improvement 3 months postoperatively: SST (P = 0.003), ASES (P = 0.006) and total CMS (P < 0.001). Three patients (17.6 %) developed a distalization of the maximum biceps circumference of more than 20 % compared to preoperative. CONCLUSIONS: All-arthroscopic proximal suprapectoral intraosseous single-limb biceps tenodesis for the treatment of isolated biceps lesions provides good-to-excellent clinical results with significant improvement of elbow flexion strength and clinical scores and no significant difference to the unaffected contralateral arm. LEVEL OF EVIDENCE: IV.

T2* mapping and delayed gadolinium-enhanced magnetic resonance imaging in cartilage (dGEMRIC) of humeral articular cartilage--a histologically controlled study.

BACKGROUND: Cartilage biochemical imaging modalities that include the magnetic resonance imaging (MRI) techniques of T2* mapping (sensitive to water content and collagen fiber network) and delayed gadolinium-enhanced MRI of cartilage (dGEMRIC, sensitive to the glycosaminoglycan content) can be effective instruments for early diagnosis and reliable follow-up of cartilage damage. The purpose of this study was to provide T2* mapping and dGEMRIC values in various histologic grades of cartilage degeneration in humeral articular cartilage. METHODS: A histologically controlled in vitro study was conducted that included human humeral head cartilage specimens with various histologic grades of cartilage degeneration. High-resolution, 3-dimensional (3D) T2* mapping and dGEMRIC were performed that enabled the correlation of MRI and histology data. Cartilage degeneration was graded according to the Mankin score, which evaluates surface morphology, cellularity, toluidine blue staining, and tidemark integrity. SPSS software was used for statistical analyses. RESULTS: Both MRI mapping values decreased significantly (P < .001) with increasing cartilage degeneration. Spearman rank analysis revealed a significant correlation (correlation coefficients ranging from -0.315 to 0.784; P < .001) between the various histologic parameters and the T2* and T1Gd mapping values. CONCLUSION: This study demonstrates the feasibility of 3D T2* and dGEMRIC to identify various histologic grades of cartilage damage of humeral articular cartilage. With regard to the advantages of these mapping techniques with high image resolution and the ability to accomplish a 3D biochemically sensitive imaging, we consider that these imaging techniques can make a positive contribution to the currently evolving science and practice of cartilage biochemical imaging.