Perfusion of the proximal scaphoid pole: correlation between preoperative ge-MRI and intraoperative findings.

BACKGROUND: Gadolinium enhanced MRI (ge-MRI) is considered as gold standard for perfusion evaluation in case of scaphoid nonunion (SNU). However, its clinical value and specificity is still not clearly evaluated. This study compares preoperative ge-MRI-based perfusion assessment and intraoperative proximal pole (PP) perfusion after scaphoid reconstruction by vascularized bone grafts. In addition, the postoperative osseous consolidation (OC) was correlated to intraoperative perfusion findings. METHODS: Between 08/2010 and 01/2020, 60 of 271 patients with scaphoid nonunion received a vascularized radius bone graft for reconstruction. Medical reports were checked for intra-op perfusion findings. Consolidation rate was assessed at mean follow-up of 3 months by CT evaluation. In 50 cases (83.2%), complete medical and radiological history could be obtained. Preoperative ge-MRI was reevaluated by a blinded radiologist for advanced analysis of sensitivity and specificity. RESULTS: Preoperative ge-MRI (initial finding, IF) showed 23 avascular, 20 malperfused, and seven vital PP. Blinded radiological follow-up (second finding, SF) revealed 14 avascular, 28 malperfused, and 8 vital PP, with a concordance of 65.3% (n = 35). After correlation with the intra-op findings, a specificity of preoperative ge-MRI of 76.5% (IF) and 88.2 (SF), respectively, was revealed for exclusion of avitality. For detection of malperfusion, there was a sensitivity of 92.7% (IF) and 85.4% (SF), respectively. Complete OC was seen 12 weeks postoperatively in 37 (73.5%), partial OC in 9 (18.3%), and nonunion in 4 cases (8.2%) on CT-scans. Of the 41 malperfused/avascular PP, 31 (75.6%) progressed to complete and 6 (14.6%) to partial (at least 2 adjacent CT-layers of 2 mm) OC, with 4 nonunions. CONCLUSION: The sensitivity and specificity of ge-MRI for detection/ exclusion of malperfusion/avitality of the PP was lower than expected. Therewith, the intraoperative assessment of PP perfusion regains a high value in decision-making for the appropriate graft. We recommend preservation of the dorsal radial vascular plexus initially until the vascularity of the proximal pole has been estimated. Patient education for all contingencies and retraction options should be obtained.

Vascularized Medial Femoral Condyle Autografts for Osteochondral Lesions of the Talus: A Preliminary Prospective Randomized Controlled Trial.

Talar osteochondral lesions (OCLs) lead to progressive stages of talar destruction. Core decompression with cancellous bone grafting (CBG) is a common treatment for Berndt and Harty stages II and III. However, in a subset of patients, talar revascularization may fail. Surgical angiogenesis using vascularized medial femoral condyle (MFC) autografts may improve on these outcomes. These 2 treatment strategies were directly compared via a prospective preliminary randomized trial including 20 participants with talar core decompression followed by either cancellous (CBG group, n = 10) or vascularized MFC (MFC group, n = 10) bone grafting. Outcome analysis was performed with visual analog scale (VAS), American Orthopaedic Foot and Ankle Society (AOFAS) ankle-hindfoot score, Lower Extremity Functional Scale (LEFS), and contrast-enhanced magnetic resonance imaging (MRI) scans. At 12 months of follow-up, the mean VAS score was reduced from 6.6 ± 2.5 preoperatively to 4 ± 1.9 in the CBG group and from 5.2 ± 2.9 preoperatively to 1 ± 1.1 in the MFC group (p < .001). The LEFS improved from 53.4 ± 13.1 to 62.6 ± 16.2 CBG and from 53 ± 9.3 to 72.4 ± 7.4 MFC (p = .114). AOFAS improved from 71 ± 12.1 to 84.1 ± 12.5 in CBG and from 70.5 ± 7.4 to 95.1 ± 4.8 in MFC (p = .019). The MRI scans in the CBG group demonstrated 9 partial malperfusions and 1 hypervascularized bone graft, whereas the MFC group had 8 well-vascularized grafts incorporated into the talus and 1 partial malperfusion. Vascularized MFC autografts provide superior pain relief along with improvement of physical function in patients with talar OCL stage II and III compared with CBG. To confirm these promising results, further multicenter randomized controlled trials are required.

Interobserver and intraobserver agreement of ligamentous injuries on conventional MRI after simple elbow dislocation.

BACKGROUND: The primary objective of this study was to assess the interobserver and intraobserver agreement on ligamentous injuries on conventional magnetic resonance imaging (MRI) in acute simple elbow dislocation. The secondary objectives were to determine the interobserver agreement on the assessment of joint congruity, joint effusion, loose bodies and chondral lesions on conventional MRI. METHODS: Conventional MRIs (1.5 Tesla, elbow specific surface coil) of 30 patients (40.7 years; range 14-72) with simple elbow dislocations were evaluated by four blinded examiners. An analysis of the interobserver agreement of all raters and for several subgroups (radiologists, orthopaedics, experienced, non-experienced) was performed. The examiners assessed the integrity (intact, partial tear, complete tear) of the lateral collateral ligament (LCL), medial collateral ligament (MCL), extensor and flexor tendons, as well as the presence of joint congruity, joint effusion, loose bodies and chondral lesions. Agreement strength, correlation and proportion of exact agreement were determined for interobserver agreement, and intraobserver agreement analyses. RESULTS: Interobserver agreement of all examiners was fair to moderate for collateral ligaments (LCL: 0.441, MCL: 0.275). Exact agreement of all raters was found in 33.3% for the LCL and in 26.7% for the MCL. The both experienced examiners showed highest agreement strength for the LCL (0.619) and the radiologists showed highest agreement strength for the MCL (0.627), the proportion of exact agreement was 60.0% in both categories. A high proportion of exact agreement regarding joint congruity (90%), joint effusion (100%), loose bodies (96.7%) and chondral lesion (80%) was found among the radiologists. The evaluation of the intraobserver agreement revealed slight to substantial agreement (0.227 to 0.718) for the collateral ligaments. CONCLUSIONS: This study shows difficulties in the evaluation of ligaments by conventional MRI technique as demonstrated by a weak inter- and intraobserver agreement. This should be the basis to develop new MRI quality standards with special focus on coronal oblique reconstructions to improve the evaluation of ligament injuries after simple elbow dislocations.

Surgical Revascularization-An Innovative Approach to the Treatment of Talar Osteonecrosis Dissecans Stages II and III.

Talar osteonecrosis dissecans is caused by osseous malperfusion, leading to destruction of the talar bone. The current reference standard for advanced stages lacking arthrosis is core decompression, followed by autologous cancellous bone grafting. However, talar revascularization has not been observed in a subset of patients after this procedure. Microsurgical vascularized bone grafting can improve outcomes by the induction of angiogenesis. We present the 1-year follow-up data from 3 patients with talar osteonecrosis dissecans, who had undergone free vascularized medial femoral condyle autotransplantation. The patients were evaluated preoperatively and 3, 6, and 12 months postoperatively. The active range of motion, pain (visual analog scale [VAS]), and American Orthopaedic Foot and Ankle Society ankle-hindfoot scale, and lower extremity functional scale were used. Osteonecrosis dissecans stage II was seen in patient 1 (aged 27 years) and stage III in patients 2 (aged 18 years) and 3 (aged 41 years). Preoperative pain of the ankle was recorded as VAS score of 3 by patients 1 and 2 and VAS score of 6 by patient 3. At 12 months postoperatively, patients 1 and 2 recorded a VAS score of 2 and patient 3, a VAS score of 0. All patients showed improvement in the lower extremity functional scale and American Orthopaedic Foot and Ankle Society scale scores. After 6 and 12 months, magnetic resonance imaging showed a well-vascularized femoral condyle incorporated into the talus in all the patients. Autotransplantation of vascularized bone grafts from the medial femoral condyle is a promising technique for surgical revascularization of talar osteonecrosis dissecans stage II and III.