International Journal of Rheumatic Diseases 2014; 17: 221–222
CORRESPONDENCE
Sonographic evidence of impingement mechanism in a patient with patellar tendon rupture after total knee replacement Dear Editor, The rupture of the patellar tendon after a total knee replacement (TKR), has been considered a devastating complication, usually followed by a challenging surgery and discouraging results.1,2 Because TKR is a procedure commonly performed in rheumatic patients with advanced disease, rheumatologists should not ignore this complication. Having a high rate of suspicion, particularly in those patients who experience pain in the patellar tendon after a TKR, is crucial. A 59-year-old man with a TKR secondary to trauma, underwent ultrasound for persistent anterior knee pain in the right knee. Physical examination showed a superiorly dislocated patella, quadriceps atrophy and a moderate-sized effusion (Fig. 1 Panel A). The range of motion was significantly compromised with 155° extension despite complete flexion.
(a)
Lateral and anterior-posterior radiographic views of the knee confirmed superior migration of the patella (Fig. 1 Panel B). Sonographic longitudinal views of the infrapatellar area showed an impingement of the infrapatellar soft tissue by the metal femoral component of the prosthesis when the knee was flexed at 100° (Fig. 2 Panel A). Otherwise, it was not present when the knee was extended at 155° (Fig. 2 Panel B). Power Doppler ultrasound (US) disclosed an intense signal of the femoral metal component (Fig. 2 Panel C), but no signal was noted on the impinged infrapatellar soft tissue and in the hypoechoic polyp-like masses. Although patellar tendon rupture is easily recognizable by a simple X-ray, we speculate that early identification of the impingement mechanism, since ultrasound has been proven to be a helpful and very sensitive tool in the detection of early changes on the
(b)
Fig. 1 Notice the quadriceps atrophy, and a lump in the thigh due to a patella superiorly dislocated, (a). Lateral and anterior-posterior radiograms showing the superior migration of the patella (b).
© 2013 Asia Pacific League of Associations for Rheumatology and Wiley Publishing Asia Pty Ltd
Correspondence
IFST
IFST e
MFC
MFC
SA
SA e
e
(a)
(b)
(c)
Fig. 2 Sonographic longitudinal views showing a moderate effusion (e) and synovial involvement possibly related to synovial adhesions (SA) in the infrapatellar area. In (a) an impingement of the infrapatellar soft tissue (IFST) by the metal femoral component (MFC) of the prosthesis at 100° is detected with the knee flexion (a). In (b) the impingement mechanism disappears during the extension of the knee. (c) Doppler signal artifact is disclosed on the metal femoral component.
tendon in patients with tendinopathy,3,4 might prevent the rupture of the tendon with an opportune therapy. Our patient, a typical case with an old rupture of the patellar tendon, obviously does not show a tendon impingement mechanism by US. Despite this, an impingement by the femoral component of the prosthesis was noted in the infrapatellar soft tissue. The absence of flow by Doppler US in the hypertrophied tissue seems related to the nature of a surgical process with the massive production of synovial adhesions, explaining the sonographic appearance of a loculated effusion and the decreased range of motion. We conclude that ultrasonography might be a promising tool to prevent a patellar tendon tear in patients who experience pain in the patellar tendon after a TKR. Although a patellar tendon friction syndrome has been characterized recently in patients with knee pain using magnetic resonance imaging (MRI),5 US is an inexpensive dynamic imaging modality which might be helpful in a similar way to MRI, detecting impingement mechanisms and early changes on the tendon.
CONFLICT OF INTEREST
Angel CHECA and Carolyn R. O’CONNOR Division of Rheumatology, Drexel University College of Medicine, Philadelphia, Pennsylvania, USA Correspondence: Dr Angel Checa, email: [email protected]
REFERENCES 1 Browne JA, Hanssen AD (2011) Reconstruction of patellar tendon disruption after total knee arthroplasty: results of a new technique utilizing synthetic mesh. J Bone Joint Sur Am 93 (12), 1137–43. 2 Lin PC, Wang JW (2007) Use of a turndown quadriceps tendon flap for rupture of the patellar tendon after total knee arthroplasty. J Arthroplasty 22 (6), 934–8. 3 Grassi W, Filippucci E, Farina A, Cervini C (2000) Sonographic imaging of tendons. Arthritis Rheum 43 (5), 969– 76. 4 Gutierrez M, Zeiler M, Filippucci E et al. (2011) Sonographic subclinical entheseal involvement in dialysis patients. Clin Rheumatol 30 (7), 907–13. 5 Chung CB, Skaf A, Roger B, Campos J, Stump X, Resnick D (2001) Patellar tendon-lateral femoral condyle friction syndrome: MR imaging in 42 patients. Skeletal Radiol 30, 694–7.
None.
222
International Journal of Rheumatic Diseases 2014; 17: 221–222
Copyright of International Journal of Rheumatic Diseases is the property of Wiley-Blackwell and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use.
Copyright of International Journal of Rheumatic Diseases is the property of Wiley-Blackwell and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use.
CORRESPONDENCE
Sonographic evidence of impingement mechanism in a patient with patellar tendon rupture after total knee replacement Dear Editor, The rupture of the patellar tendon after a total knee replacement (TKR), has been considered a devastating complication, usually followed by a challenging surgery and discouraging results.1,2 Because TKR is a procedure commonly performed in rheumatic patients with advanced disease, rheumatologists should not ignore this complication. Having a high rate of suspicion, particularly in those patients who experience pain in the patellar tendon after a TKR, is crucial. A 59-year-old man with a TKR secondary to trauma, underwent ultrasound for persistent anterior knee pain in the right knee. Physical examination showed a superiorly dislocated patella, quadriceps atrophy and a moderate-sized effusion (Fig. 1 Panel A). The range of motion was significantly compromised with 155° extension despite complete flexion.
(a)
Lateral and anterior-posterior radiographic views of the knee confirmed superior migration of the patella (Fig. 1 Panel B). Sonographic longitudinal views of the infrapatellar area showed an impingement of the infrapatellar soft tissue by the metal femoral component of the prosthesis when the knee was flexed at 100° (Fig. 2 Panel A). Otherwise, it was not present when the knee was extended at 155° (Fig. 2 Panel B). Power Doppler ultrasound (US) disclosed an intense signal of the femoral metal component (Fig. 2 Panel C), but no signal was noted on the impinged infrapatellar soft tissue and in the hypoechoic polyp-like masses. Although patellar tendon rupture is easily recognizable by a simple X-ray, we speculate that early identification of the impingement mechanism, since ultrasound has been proven to be a helpful and very sensitive tool in the detection of early changes on the
(b)
Fig. 1 Notice the quadriceps atrophy, and a lump in the thigh due to a patella superiorly dislocated, (a). Lateral and anterior-posterior radiograms showing the superior migration of the patella (b).
© 2013 Asia Pacific League of Associations for Rheumatology and Wiley Publishing Asia Pty Ltd
Correspondence
IFST
IFST e
MFC
MFC
SA
SA e
e
(a)
(b)
(c)
Fig. 2 Sonographic longitudinal views showing a moderate effusion (e) and synovial involvement possibly related to synovial adhesions (SA) in the infrapatellar area. In (a) an impingement of the infrapatellar soft tissue (IFST) by the metal femoral component (MFC) of the prosthesis at 100° is detected with the knee flexion (a). In (b) the impingement mechanism disappears during the extension of the knee. (c) Doppler signal artifact is disclosed on the metal femoral component.
tendon in patients with tendinopathy,3,4 might prevent the rupture of the tendon with an opportune therapy. Our patient, a typical case with an old rupture of the patellar tendon, obviously does not show a tendon impingement mechanism by US. Despite this, an impingement by the femoral component of the prosthesis was noted in the infrapatellar soft tissue. The absence of flow by Doppler US in the hypertrophied tissue seems related to the nature of a surgical process with the massive production of synovial adhesions, explaining the sonographic appearance of a loculated effusion and the decreased range of motion. We conclude that ultrasonography might be a promising tool to prevent a patellar tendon tear in patients who experience pain in the patellar tendon after a TKR. Although a patellar tendon friction syndrome has been characterized recently in patients with knee pain using magnetic resonance imaging (MRI),5 US is an inexpensive dynamic imaging modality which might be helpful in a similar way to MRI, detecting impingement mechanisms and early changes on the tendon.
CONFLICT OF INTEREST
Angel CHECA and Carolyn R. O’CONNOR Division of Rheumatology, Drexel University College of Medicine, Philadelphia, Pennsylvania, USA Correspondence: Dr Angel Checa, email: [email protected]
REFERENCES 1 Browne JA, Hanssen AD (2011) Reconstruction of patellar tendon disruption after total knee arthroplasty: results of a new technique utilizing synthetic mesh. J Bone Joint Sur Am 93 (12), 1137–43. 2 Lin PC, Wang JW (2007) Use of a turndown quadriceps tendon flap for rupture of the patellar tendon after total knee arthroplasty. J Arthroplasty 22 (6), 934–8. 3 Grassi W, Filippucci E, Farina A, Cervini C (2000) Sonographic imaging of tendons. Arthritis Rheum 43 (5), 969– 76. 4 Gutierrez M, Zeiler M, Filippucci E et al. (2011) Sonographic subclinical entheseal involvement in dialysis patients. Clin Rheumatol 30 (7), 907–13. 5 Chung CB, Skaf A, Roger B, Campos J, Stump X, Resnick D (2001) Patellar tendon-lateral femoral condyle friction syndrome: MR imaging in 42 patients. Skeletal Radiol 30, 694–7.
None.
222
International Journal of Rheumatic Diseases 2014; 17: 221–222
Copyright of International Journal of Rheumatic Diseases is the property of Wiley-Blackwell and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use.
Copyright of International Journal of Rheumatic Diseases is the property of Wiley-Blackwell and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use.
