Periosteal stripping of the MCL Poster o.: P-0014 Congress: ESSR 2016 Type: Educational Poster Authors: R. Pedersen; Toensberg/O Keywords: Musculoskeletal soft tissue, Musculoskeletal joint, Anatomy, MR, Imaging sequences, Athletic injuries DOI: 10.1594/essr2016/P-0014 Any information contained in this pdf file is automatically generated from digital material submitted to EPOS by third parties in the form of scientific presentations. References to any names, marks, products, or services of third parties or hypertext links to thirdparty sites or information are provided solely as a convenience to you and do not in any way constitute or imply ECR's endorsement, sponsorship or recommendation of the third party, information, product or service. ECR is not responsible for the content of these pages and does not make any representations regarding the content or accuracy of material in this file. As per copyright regulations, any unauthorised use of the material or parts thereof as well as commercial reproduction or multiple distribution by any traditional or electronically based reproduction/publication method ist strictly prohibited. ou agree to defend, indemnify, and hold ECR harmless from and against any and all claims, damages, costs, and expenses, including attorneys' fees, arising from or related to your use of these pages. Please note: Links to movies, ppt slideshows and any other multimedia files are not available in the pdf version of presentations. www.essr.org Page 1 of 25
Learning objectives The combination of rupture of the PCL and medial stripping of periost from the femoral epicondyle (figure 1 and 2) presents a peculiar finding that may confuse the radiologist and clinician. This poster presents a summary of these findings, as well as an analysis of 13 cases. Images for this section: Fig. 1: Patient #1. Arrows show ruptured PCL, in the middle part of the ligament. Page 2 of 25
Fig. 2: Patient #1, same as in fig. 1. Multiple arrows show MCL and medial epicondylar periosteum as a continuous structure, the MCL is avulsed from the epicondyle. Single arrow points at ruptured PCL. Page 3 of 25
Background In an article from 2009 (reference 1), McAnally et al discussed the association of PCL injury and medial femoral epicondylar periosteal stripping. Their article reviewed four cases with these findings, where avulsion of the medial collateral ligament were seen in continuation proximally with periosteum of the medial femoral epicondyle. The authors stated that "the incidence of this pattern is uncertain", and "this may be a more common occurence than we realize that has been previously overlooked". In three of the four cases there were "subsequent development of heterotopic bone formation about the medial femoral epicondyle, with the classic appearance of PellegriniStieda". The authors propose that periosteal stripping may be one possible cause for Pellegrini-Stieda. In this poster, 13 cases of rupture of the PCL and associated medial femoral epicondylar periosteal stripping is reviewed (figure 3 and 4). This represents a larger material than the above mentioned article, and associated findings are discussed. Images for this section: Page 4 of 25
Fig. 3: Pasient #2. Rupture of PCL, in the middle part. Fig. 4: Patient #2, same as in fig. 3. Medial epicondylar periosteal stripping, in continuation with an avulsed MCL. Page 5 of 25
Imaging findings OR Procedure Details Method 13 cases imaged with MRI in the period september 2009 to february 2016 were reviewed. 1 case was retrospectively identified at images from 2009, the other 12 identified incidentally and randomly during the years 2013-2016. 4 of these cases had follow-up investigations. The images were analyzed for the presence of injury to the PCL, periosteal stripping from the medial femoral epicondyle, edema of the lateral femoral condyle, injury to the lateral collateral ligament (LCL), injury to the medial meniscofemoral ligament, and rupture of the menisci. Information about trauma, and time between trauma and imaging were also noted. This information was based on the original written referrals. Pat no Study Follow dmcl Edema PCL up rupt lat rupt. / fem / 1 10/13 2 02/13 3 LCL Rupt / Menisc Age / TraumaTime between imaging and trauma, days/ weeks Middle 50 Torsion 2 w Middle 32 Skiing 2 w 11/13 Distal 24 Torsion 10 w 4 03/14 Distal 38 Fall 3w from ladder 5 04/14 08/14 Middle 17 Fall at 4 d trampoline 6 02/14 06/14 Middle 17 Fall 2d while downhill skiing 7 11/14 Entire 20 Torsion 8 w at soccer 8 01/15 Distal Flap, Deg. 77 Unknown /A 11/13 Page 6 of 25
9 12/15 Distal Deg. 46 Torsion 1 w at walking 10 09/09 Distal 33 Unknown /A 11 02/16 Entire 16 Fall 1w at ice hockey 12 02/16? Bucket 54 handle Unknown /A 13 03/16 One bundle Snowboard 7w 01/16 47 Findings 10 male and 3 female patients were analyzed. The mean age was 36 years, but 8 of the patients were younger than 40 years. The oldest patient was 77, the youngest 16 years (fig. 5 and 6). 3 of the patients could not identify a specific trauma. 6 patients sustained a fall during sports. 1 fell from a ladder, and 3 patients sustained fall trauma or torsion during everyday activity (fig. 7, 8 and 9). The 10 patients with an indentifiable trauma were imaged after trauma after a mean time of 24 days. 1 patient was imaged after 2 days, 1 patient after 10 weeks. All of the patients presented with periosteal stripping from the medial femoral epicondyle. The MCL was in continuation with the stripped periosteum, the proximal attachment of the MCL was therefore avulsed from the epicondyle (fig. 10). 12 of 13 patients presented with PCL rupture. The ruptures were evaluated to be in the middle part (4/12), distal part (5/12), in the entire ligament (2/12), and in one bundle of the ligament (1/12) (fig. 11-14). 12 of the 13 patients presented with bone marrow edema of the lateral femoral condyle, near the proximal attachment of the LCL (fig. 15). There were proximal signal changes in the LCL suggesting partial rupture or strain in 5 of 13 patients (fig. 16). 12 of 13 patients presented with findings suggesting proximal avulsion of the medial meniscofemoral ligament, the deep part of the medial collateral ligament complex (fig. 17 and 18). 3 patients were identified with meniscal rupture, 1 with degenerative rupture and a flap fragment, 1 with only degenerative medial meniscal rupture, and 1 with degenerative Page 7 of 25
rupture and a bucket handle rupture. Of note, all the other 10 patients did not have meniscal lesions/rupture. 1 patient presented with medial periosteal stripping, but with no certain rupture of the PCL, medial meniscofemoral ligament nor edema of the lateral femoral condyle. However, this patient had findings of a partial rupture of the LCL, degenerative rupture of the medial meniscus and also a bucket handle meniscal fragment. There was no identified trauma, and no information about time between a possible insult and imaging. This patient may have sustained a different injury than the other patients (fig. 16). Findings at follow up studies 4 of 13 patients were imaged again at our institution, all of these with MRI. The patients were imaged after 4 months (2 patients), 9 months (1 patient) and 5 years and 4 months (1 patient). At follow-up, 3 of the cases showed normalization, with close apposition of the periost to the femur, and no additional changes (fig. 18 and 19). o calcifications were detected. The fourth case (number 10) showed edema at the medial femoral epicondyle and probably a new injury to the insertion of the periost and MCL. The previous imaging was performed in 2009, the follow-up in 2016, the reason being a new trauma. This patient probably experienced the same trauma twice. Discussion Our findings suggest a strong association between rupture of the PCL, avulsion of the proximal insertion of MCL and stripping of the epicondylar periosteum, the MCL and periosteum found to be in continuation along the medial femur. McAnally's article proposes a merging of fibers between MCL and periost, which seems likely given the imaging findings. There was also a strong association between these findings and a rupture of the proximal insertion of the medial meniscofemoral ligament. Furthermore a strong association with edema of the lateral femoral condyle near the attachment of LCL, and in 5 cases signal changes in the proximal part of the LCL suggesting partial rupture or at least a strain of the ligament. It seems likely that these patients sustained a torsion of the knee, but the mechanism of injury were not sufficiently described in neither of the cases, so no strong conclusions could be made. The findings suggest rotational forces acting on the PCL, the LCL, the medial meniscofemoral ligament, the medial collateral ligament and the periosteal attachment. A possible explanation for the findings could be that a PCL injury makes the knee unstable for rotational forces and that the other findings were secondary, from a later injury. However, the short time span between injury and imaging in some of the patients makes it unlikely that the findings were the result of more than one injury. Page 8 of 25
The follow up imaging of 4 patients revealed a normalization in three of the patients at the medial side of the knee, with resolution of the initial changes. o patients were subject to surgery to the MCL and periosteum, and no calcifications could be identified. However, the observation time was limited. Images for this section: Fig. 5: Patient #11. 16 yo male. Ice hockey injury. The entire PCL is injured. Page 9 of 25
Fig. 6: Patient #11, same as in fig. 5. 16 yo male. Ice hockey injury. Medial epicondylar periosteal stripping. Page 10 of 25
Fig. 7: Patient #7. Soccer inury. This image shows medial epicondylar periosteal stripping, edema of the lateral femoral condyle and ruptured PCL. Page 11 of 25
Fig. 8: Patient #4. Fall from ladder. This image shows medial epicondylar periosteal stripping, injury to the PCL and avulsion of the deep part of the MCL (dmcl). Page 12 of 25
Fig. 9: Patient #9. Injury while walking, sudden torsion. This image shows edema of the lateral femoral condyle, avulsion of the dmcl and medial epicondylar periosteal stripping. Page 13 of 25
Fig. 10: Patient #11. This slightly enlarged image shows the continuation of MCL and stripped epicondylar periosteum. Page 14 of 25
Fig. 11: Patient #5. Rupture of the PCL in the middle part. Page 15 of 25
Fig. 12: Patient #8. Rupture of the PCL in the distal part. Page 16 of 25
Fig. 13: Patient #13. Rupture of one bundle of the PCL. Arrows point to a dark intact bundle and a brighter ruptured bundle. Page 17 of 25
Fig. 14: Patient #13, same as in fig. 14. Rupture of one bundle of the PCL. Arrows point to a dark intact bundle and a brighter ruptured bundle. Page 18 of 25
Fig. 15: Patient #9. Edema of the lateral femoral condyle. Page 19 of 25
Fig. 16: Patient #12. Hyperintense signal of the proximal LCL, indicating injury. Page 20 of 25
Fig. 17: Patient #1. Medial periosteal epicondylar stripping and PCL rupture. Page 21 of 25
Fig. 18: Same patient as in fig 17. On a slightly more anterior slice, avulsion of the proximal insertion of dmcl is noted. Page 22 of 25
Fig. 19: Patient #5. Initial MR shows medial epicondylar periosteal stripping and edema of the lateral femoral condyle. Page 23 of 25
Fig. 20: Same patient as in fig 19. After 4 months of conservative treatment, the periosteum and MCL insertion are closely apposed to the medial femoral condyle. Page 24 of 25
Conclusion The analysis of 13 cases with rupture of the PCL and periosteal stripping of the medial femoral epicondyle confirms the findings of McAnally et al. Our cases suggest additonal associated findings of avulsion of the medial meniscofemoral ligament, edema of bone marrow at the proximal insertion of the LCL, and to a varying degree strain or rupture of the LCL. The combination of findings may be the result of a torsion of the knee, but the unprecise anamnestic information in our cases does not allow any strong conclusions to be made regarding mechanism of injury. The cases were incidentally collected during a period of several years, and the real incidence is not established. However, we agree with the assumption of McAnally et al that this injury and combination of findings may be under-recognized. References 1. McAnally JL, Southam SL, Mlady GW. ew thoughts on the origin of Pelegrini-Stieda: the association of PCL injury and medial femoral epicondylar periosteal stripping. Skeletal Radiol 2009;38(2):193-198 Personal Information The author is a MSK subspeciality radiologist working at Curato Røntgen orway. Page 25 of 25