Magnetic resonance imaging for supraspinatus muscle atrophy after cuff repair

Between 1998 to 2000, the shoulders of 17 patients with rotator cuff tears were examined using magnetic resonance imaging preoperatively, and 6 and 12 months after open surgical repair. To assess the course of the supraspinatus muscle atrophy, the easily reproducible magnetic resonance imaging parameters occupation ratio and tangent sign in the Y-shaped view of the supraspinous fossa were evaluated and compared with the clinical examination. Occupation ratio is a quantitative parameter that reflects the area ratio, expressed as a percentage of the supraspinatus muscle belly to the supraspinous fossa. The tangent sign is a qualitative parameter that represents a line connecting the coracoid process and the apex of the scapular spine. Occupation ratio and tangent sign are reliable diagnostic tools in magnetic resonance imaging assessment of supraspinatus muscle atrophy. The sensitivity of the magnetic resonance imaging parameter occupation ratio is 75% and the specificity is 85%. The imaging parameter tangent sign has a sensitivity of 100% and a specificity of 85%. There is a significant relationship between occupation ratio, tangent sign, and improvement of strength and mobility registered in the score of Constant and Murley 12 months after surgery.     

Volume changes of supraspinatus and infraspinatus muscles after supraspinatus tendon repair: a magnetic resonance imaging study

Muscle volume was measured, by use of magnetic resonance imaging (MRI), as a direct indicator of functional recovery of the supraspinatus and infraspinatus muscles after supraspinatus tendon repair, because atrophy of the supraspinatus and infraspinatus muscles was observed in all patients with a torn supraspinatus tendon. Seventy-three patients who had a cuff tear limited only to the supraspinatus tendon were included in this study. The University of California, Los Angeles score improved significantly after surgery. MRI was carried out before surgery and 6, 12, and 24 months postoperatively in all patients. Muscle volume of the supraspinatus was assessed on images of the oblique coronal plane, and that of the infraspinatus was assessed on images of the axial plane. The width of the supraspinatus muscle did not recover until 6 months postoperatively. Direct measurement of the infraspinatus muscle volume by use of MRI can be a good indicator when evaluating whether the repaired rotator cuffs are actually functioning.     

Prospective randomised comparison of arthroscopic versus mini-open rotator cuff repair of the supraspinatus tendon

Purpose  

The aim of the study was to evaluate whether arthroscopic (ASC) repair of rotator cuff ruptures causes less postoperative pain and better range of motion (ROM) in the early postoperative period than a mini-open (MO) technique.     

Magnetic resonance imaging of cartilage repair techniques

Magnetic resonance (MR) imaging offers a noninvasive method to assess cartilage repair, allowing objective evaluation of the repair tissue and insight into the natural history of cartilage repair procedures. MR imaging allows assessment of the percent fill, signal morphology of the repair tissue, subchondral bone and three-dimensional geometry of the joint. The information gained from MR imaging therefore plays a valuable role in patient follow-up after cartilage repair. This article discusses the MR imaging techniques available for the assessment of articular cartilage, including quantitative imaging techniques that allow assessment of cartilage biochemistry. The MR imaging appearance and assessment of microfracture, autologous chondrocyte implantation, and osteochondral autograft and allograft transplantation is reviewed.     

Comparing shoulder maneuvers to magnetic resonance imaging and arthroscopic findings in patients with supraspinatus tears

BACKGROUNDShoulder maneuvers and magnetic resonance imaging (MRI) are performed to diagnose supraspinatus tendon tears regardless of arthroscopy exam. Although there are many studies on this subject, there is a lack of studies comparing the sensitivity (Se) and specificity (Sp) of shoulder maneuvers and MRI to arthroscopic findings (intact, partial, or full thickness supraspinatus tendon tear).AIMTo compare the diagnostic values of shoulder maneuvers with MRI for supraspinatus tendon tears in patients undergoing shoulder arthroscopy.METHODSA total of 199 consecutive patients from four orthopedic centers met the eligibility criteria of shoulder pain persisting for at least four weeks. They were prospectively enrolled in this study from April 2017 to April 2019. Seven clinical tests (full can, empty can, drop arm, Hawkins’, painful arc, Neer’s sign and resisted external rotation) and MRI were performed, and all were compared with surgical findings. Full can, empty can and resisted external rotation tests were interpreted as positive in the case of pain and/or weakness. We assessed the Se, Sp, accuracy, positive predictive value (PPV) and negative predictive value (NPV), positive and negative likelihood ratio and diagnostic odds ratio for overall, partial and full-thickness supraspinatus tears.RESULTSMRI had the highest Se for overall (0.97), partial (0.91) and full-thickness (0.99) tears; moreover, MRI had the highest NPV: 0.90, 0.88 and 0.98 for overall, partial and full-thickness tears, respectively. For overall supraspinatus tears, the Se and PPV were: Painful arc (Se = 0.85/PPV = 0.91), empty can (pain) (Se = 0.80/PPV = 0.89), full can (pain) (Se = 0.78/PPV = 0.90), resisted external rotation (pain) (Se = 0.48/PPV = 0.87), drop arm (Se = 0.19/PPV = 0.97), Neer’s sign (Se = 0.78/PPV = 0.93) and Hawkins’ (Se = 0.80/PPV = 0.88). MRI had the highest PPV (0.99). The Hawkin’s test had the highest false positive rate in patients with intact tendons (0.36). The Sp of the empty can and full can (both tests positive for pain and weakness), drop arm and MRI were: 0.93, 0.91, 0.98 and 0.96, respectively. For partial and full-thickness tears, the empty can test (positive for pain and weakness) had a Sp of 0.93, and the drop arm and MRI had the same Sp (0.98).CONCLUSIONPhysical examination demonstrated good diagnostic value, the drop arm test had a Sp as good as MRI for supraspinatus tears; however, MRI was more accurate in ruling out tears. The Hawkins’ test had high false-positive findings in patients with intact tendons.     

Magnetic resonance imaging of tibial shaft fracture repair

Summary Magnetic resonance imaging (MRI) of normal fracture repair was evaluated in six randomly chosen adult patients with solitary, closed fractures of the tibial shaft by obtaining serial MRI scans until union of the fracture. The mean time to union was 14.3 weeks. Ultralow-field 0.02-Tesla magnet equipment was used. The MRI scans showed a characteristic pattern of events common for all the patients studied and compatible with the recognized histomorphology of fracture repair. The intramedullary cavity demonstrated a marked decrease in the signal intensity. In the soft tissues surrounding the fracture the initially evenly high signal intensity gradually developed a granular appearance with embedded low-intensity nodules. These nodules corresponded to the first areas to become mineralized, as could be seen on plain radiographs several weeks later. The question of whether MRI renders it possible to predict delayed union calls for continued investigations.     

Comparison of two arthroscopic repair techniques for small-medium supraspinatus tendon tear: 1 triple-loaded vs 2 double-loaded metallic sutures anchors

IntroductionSurgical repair of the rotator cuff is based on the use of anchors whose ideal numbers and configurations continue to be controversial. We compared the clinical-functional results arising from the arthroscopic repair of shoulders, with small-medium lesions of the supraspinatus tendon, among patients using one anchor with three sutures, or two anchors with two sutures.MethodsIn this retrospective study patient were resolved into 2 groups. Clinical and functional results were assessed based on Constant Score and instrumental isometric examination.ResultsPatients in Group 1 experienced shoulder repair using a single anchor with three sutures (n = 21, mean age = 56 years, range = 51–65). In Group 2, patients received two anchors with two sutures each (n = 24, mean age = 59 years, range = 24–75). The mean follow-up time was 15 months. The mean values of the operated shoulders’ Constant Score were 88.05 and 88.25 respectively. Examination of isometric test results in operated shoulders, healthy shoulders and the two different rotator cuff repair techniques did not reveal any statistically significant differences.ConclusionIn the arthroscopic repair of small-medium supraspinatus tendon tears, the short to mid-term clinical and functional outcomes arising from use of 1 triple-loaded or 2 double-loaded metallic sutures anchors are comparable.     

Magnetic resonance imaging appearance of cartilage repair in the knee

Assessment of surgically repaired cartilage lesions with standardized cartilage sensitive magnetic resonance imaging was done to evaluate the integrity, morphologic features, and signal of the articular surface, thereby obtaining information about the natural history of these procedures in the knee. Magnetic resonance imaging also assessed the interface between the repaired and native cartilage, changes in the subchondral bone, and the appearance of cartilage over the opposite and adjacent (native) surfaces. One hundred eighty magnetic resonance imaging examinations were obtained in 112 patients who had cartilage-resurfacing procedures, including 86 microfractures and 35 autologous chondrocyte implantations, at a mean of 15 and 13 months after surgery, respectively. Autologous chondrocyte implantations showed consistently better fill of the defects at all times compared with microfracture. The graft hypertrophied in 63% of surgeries. The repair cartilage over the microfracture generally was depressed with respect to native cartilage. Propensity for bony overgrowth was most marked in the microfracture group, with loss of adjacent cartilage evident with progressive followup.     

肩关节镜下清理治疗钙化性冈上肌腱炎的疗效分析

[目的]探讨肩关节镜下清理冈上肌腱内钙化灶治疗钙化性冈上肌腱炎的手术疗效。[方法]自2010年1月～2011年7月对在本院就诊的9例确诊为钙化性冈上肌腱炎的患者行肩关节镜下清理冈上肌腱内钙化灶治疗,术前患者肩关节疼痛剧烈伴活动受限,经正规保守治疗3个月以上无效。术中清理肩峰下间隙,切除炎性滑囊,常规行肩峰成形术,彻底清理冈上肌腱内的钙化灶。术前及术后随访均采用VAS疼痛评分、Constant-Murley评分和X线检查对患者进行评估并做手术前后的对比分析。[结果]术后平均随访6个月,所有患者肩关节疼痛及活动受限均得到明显改善或完全缓解,VAS疼痛评分术前(8.33±1.0)分,术后最后一次复查为(1.44±0.88)分,术前、术后VAS评分差异有统计学意义(P<0.01)。Constant-Murley评分术前为(50.44±10.06)分,术后最后一次复查为(93±4.21)分,术前、术后Constant-Murley评分差异有统计学意义(P<0.01)。术后复查X线片显示冈上肌腱内钙化灶均已完整清除。[结论]关节镜下行冈上肌腱内钙化灶清理,具有手术创伤小、病灶清除彻底、对肩袖及盂肱关节损伤小、术后康复快等优点,临床疗效确切。     

Magnetic resonance imaging and histology of repair in femoral head osteonecrosis

Different repair processes affect the clinical course of nontraumatic avascular femoral head osteonecrosis, not just necrotic lesion size and location. Fourteen femoral heads were retrieved at total hip arthroplasty after core decompression treatment, or after conservative treatment was done on 13 male patients diagnosed with different stages of femoral head osteonecrosis. To determine repair types, features of coronal magnetic resonance images were correlated with light microscopy findings on corresponding coronal undecalcified sections and microradiographs of the retrieved femoral heads. In five femoral heads, repair of necrotic bone and marrow remained restricted to the reactive interface for as many as 63 months, producing the diagnostic osteosclerotic rim with adjacent hypervascularity (limited repair). Nine femoral heads showed extension of the repair process into the necrosis. In five femoral heads, predominant resorption of necrotic bone led to femoral head breakdown within 2 to 50 months (destructive repair). In four femoral heads, reparative bone formation had started from subchondral fractures and/or the reactive interface, definitely reducing the size of the necrotic area (reconstructive repair). In the latter, the disease progressed slowly or stopped for as many as 45 months, irrespective of treatments, but elimination of risk factors seemed beneficial. Although core decompression did not always reach the necrotic area and improve repair, it reduced accompanying bone marrow edema and could delay the disease progress. Osteonecrosis with limited repair can be identified on magnetic resonance images obtained at followup, but the similar signal changes of destructive and reconstructive repair cannot be distinguished on magnetic resonance images alone. The evidence of reconstructive repair in nontraumatic osteonecrosis, however, gives hope for treatments that can improve repair to a sufficient creeping substitution of the affected femoral head.     

Accelerated rehabilitation after arthroscopic meniscal repair: A clinical and magnetic resonance imaging evaluation

Twenty-two patients who underwent meniscal repair using the outside-in technique combined with anterior cruciate ligament (ACL) reconstruction were submitted to an accelerated rehabilitation protocol that included immediate full range of motion and weightbearing. The patients were reviewed postoperatively by means of clinical assessment and magnetic resonance imaging (MRI) after an average of 28 months. Clinical evaluation was performed according to the International Knee Documentation Committee form, and sagittal knee laxity was measured with a KT-2000 arthrometer (MedMetric Corp, San Diego, CA). The MRI scans were obtained using a 0.2-T high-resolution MRI unit dedicated to the study of limbs, and the meniscal signal was graded according to a modified Crues classification. Overall, 77.3% of patients reported clinically good results. Loss of extension of <5° was detected in only 2 patients (9.1%). Three out of 22 patients showed clinical signs of meniscal retear. One of these patients had a second operation for a bucket-handle tear. The presence of a full-thickness rim at MRI evaluation, present in 10 patients (45.5%), did not correlate with the presence of clinical symptoms of retear. Instead, the 3 symptomatic patients presented a complete rim with a gap>1 mm between the meniscal wall and the fragment of the posterior horn. This finding is believed to be a more reliable indicator for retear following meniscal repair. The low failure rate in this series suggests that an aggressive rehabilitation regimen may be prescribed without deleterious effects in subjects undergoing ACL reconstruction and concomitant meniscus repair.     

In situ transtendon repair outperforms tear completion and repair for partial articular-sided supraspinatus tendon tears

This biomechanical study compared 2 repair techniques for high-grade, partial, articular-sided supraspinatus tendon tears of the rotator cuff: transtendon in situ repair and tear completion with repair. Standardized, 50% partial, articular-sided supraspinatus lesions were created in 10 pairs of matched fresh, frozen cadaveric shoulders: 10 underwent partial lesion repair with an in situ transtendon technique using 2 suture anchors. In the contralateral 10 shoulders, the partial lesion was converted to a full-thickness tear and repaired with a double-row technique, using 4 suture anchors. Cyclic loading to failure of the supraspinatus tendon was performed using a material testing machine. Gap formation was measured for each rotational position and each incremental load. The in situ transtendon repair had statistically significant less gapping (P = .0001) and higher mean ultimate failure strength (P = .0011) than the double-row repair. In situ transtendon repair was biomechanically superior to tear completion for partial, articular-sided supraspinatus tears.     

Magnetic resonance imaging evaluation and arthroscopic resection of localized pigmented villonodular synovitis of the knee

Diagnosis of localized pigmented villonodular synovitis is clinically difficult, and plain radiographs are usually normal. This article presents five patients with localized pigmented villonodular synovitis of the knee. Symptoms suggested a meniscal lesion in three patients and a loose body in two. Magnetic resonance imaging performed prior to arthroscopic resection revealed a preoperative diagnosis of a tumor in all five patients. Magnetic resonance imaging is a valuable clinical tool for the assessment of intra-articular soft-tissue tumors of the knee that may otherwise be misdiagnosed.