Limits...
Pseudo-patella baja after total knee arthroplasty.

Kazemi SM, Daftari Besheli L, Eajazi A, Miniator Sajadi MR, Okhovatpoor MA, Farhang Zanganeh R, Minaei R - Med. Sci. Monit. (2011)

Bottom Line: The average follow-up was 27.5 months.KSS was lower in groups B and C compared with group A, but this difference was not statistically significant.Furthermore, KSS in the PPB group was less than in patients without PPB, although the difference was not statistically meaningful.

View Article: PubMed Central - PubMed

Affiliation: Akhtar Orthopaedic Research Center, Shahid Beheshti Medical University, Tehran, Iran.

ABSTRACT

Background: One of the complications of total knee arthroplasty (TKA) which has not yet been directly addressed is pseudo-patella baja (PPB). True patella baja (PB) is present when the length of the patellar tendon becomes shorter. PPB is present when the patella tendon is not shortened, but the level of the joint line is elevated. This study was conducted to assess PPB in TKA.

Material/methods: Sixty patients who had had a primary TKA at our center between 1995 and 2005 were included. The average follow-up was 27.5 months. The Knee Society Scoring (KSS), lateral knee x-rays and the Blackburne-Peel index were used for assessments.

Results: Out of the 60 patients, 43 (72%) demonstrated no joint line elevation or patellar tendon shortening (group A). Fifteen patients (25%) had joint line elevation (group B), and both PB and PPB were present in 2 (3%) patients (group C). KSS was lower in groups B and C compared with group A, but this difference was not statistically significant. The average range of motion (ROM) in group A was significantly higher compared with either group B or C, and patients in groups B and C showed significantly more severe pain compared with group A (P<0.001).

Conclusions: PPB is not an uncommon finding after TKA and is associated with a statistically significant decrease in ROM and an increase in pain. Furthermore, KSS in the PPB group was less than in patients without PPB, although the difference was not statistically meaningful.

Show MeSH

Related in: MedlinePlus

Blackburne-Peel index, the distance from the inferior border of the patellar articular surface to the tibiofemoral joint line (c) divided by the length of patellar articular surface (d).
© Copyright Policy
Related In: Results  -  Collection


getmorefigures.php?uid=PMC3539587&req=5

f2-medscimonit-17-5-cr292: Blackburne-Peel index, the distance from the inferior border of the patellar articular surface to the tibiofemoral joint line (c) divided by the length of patellar articular surface (d).

Mentions: As the length of the patellar tendon is normal in PPB, the use of the Insall Salvati ratio will not be appropriate; instead a different ratio that focuses on the joint line level must be considered. Therefore to look for PPB, we preferred the Blackburne-Peel index (BPI <0.54 defined PPB). The Blackburne-Peel ratio is the ratio of the distance between the inferior border of the patellar articular surface and the tibiofemoral joint line to the length of the patellar articular surface (Figure 2). The ratio becomes smaller as the joint line is raised. As the length of the patellar tendon is normal in PPB, this index, which takes the position of the joint line into account, is more appropriate [16].


Pseudo-patella baja after total knee arthroplasty.

Kazemi SM, Daftari Besheli L, Eajazi A, Miniator Sajadi MR, Okhovatpoor MA, Farhang Zanganeh R, Minaei R - Med. Sci. Monit. (2011)

Blackburne-Peel index, the distance from the inferior border of the patellar articular surface to the tibiofemoral joint line (c) divided by the length of patellar articular surface (d).
© Copyright Policy
Related In: Results  -  Collection

Show All Figures
getmorefigures.php?uid=PMC3539587&req=5

f2-medscimonit-17-5-cr292: Blackburne-Peel index, the distance from the inferior border of the patellar articular surface to the tibiofemoral joint line (c) divided by the length of patellar articular surface (d).
Mentions: As the length of the patellar tendon is normal in PPB, the use of the Insall Salvati ratio will not be appropriate; instead a different ratio that focuses on the joint line level must be considered. Therefore to look for PPB, we preferred the Blackburne-Peel index (BPI <0.54 defined PPB). The Blackburne-Peel ratio is the ratio of the distance between the inferior border of the patellar articular surface and the tibiofemoral joint line to the length of the patellar articular surface (Figure 2). The ratio becomes smaller as the joint line is raised. As the length of the patellar tendon is normal in PPB, this index, which takes the position of the joint line into account, is more appropriate [16].

Bottom Line: The average follow-up was 27.5 months.KSS was lower in groups B and C compared with group A, but this difference was not statistically significant.Furthermore, KSS in the PPB group was less than in patients without PPB, although the difference was not statistically meaningful.

View Article: PubMed Central - PubMed

Affiliation: Akhtar Orthopaedic Research Center, Shahid Beheshti Medical University, Tehran, Iran.

ABSTRACT

Background: One of the complications of total knee arthroplasty (TKA) which has not yet been directly addressed is pseudo-patella baja (PPB). True patella baja (PB) is present when the length of the patellar tendon becomes shorter. PPB is present when the patella tendon is not shortened, but the level of the joint line is elevated. This study was conducted to assess PPB in TKA.

Material/methods: Sixty patients who had had a primary TKA at our center between 1995 and 2005 were included. The average follow-up was 27.5 months. The Knee Society Scoring (KSS), lateral knee x-rays and the Blackburne-Peel index were used for assessments.

Results: Out of the 60 patients, 43 (72%) demonstrated no joint line elevation or patellar tendon shortening (group A). Fifteen patients (25%) had joint line elevation (group B), and both PB and PPB were present in 2 (3%) patients (group C). KSS was lower in groups B and C compared with group A, but this difference was not statistically significant. The average range of motion (ROM) in group A was significantly higher compared with either group B or C, and patients in groups B and C showed significantly more severe pain compared with group A (P<0.001).

Conclusions: PPB is not an uncommon finding after TKA and is associated with a statistically significant decrease in ROM and an increase in pain. Furthermore, KSS in the PPB group was less than in patients without PPB, although the difference was not statistically meaningful.

Show MeSH
Related in: MedlinePlus