Patellofemoral MRI Alterations Following Single Bundle ACL Reconstruction with Hamstring Autografts Are Associated with Quadriceps Femoris Atrophy

High incidence of patellofemoral pain and patellofemoral joint osteoarthritis was found following anterior cruciate ligament(ACL)reconstruction.The unstability of patellofemoral joint might be an important contribution factor.This study was designed to define the relationship between the unstability of patellofemoral joint and quadriceps femoris atrophy.Twenty patients underwent MRI scan before ACL reconstruction and every two weeks after surgery,until 12 weeks.The merchant’s patellar congruence angle,lateral inclination angle,and quadriceps femoris muscle cross-sectional area were measured and the relationship between the changes of angles and the ratio of quadriceps femoris atrophy was studied by multiple regression analysis.Significant quadriceps femoris atrophy was observed after ACL reconstruction during the follow-up period of 12 weeks.The merchant’s patellar congruence angle and lateral inclination angle significantly changed after surgery.The alterations of the merchant’s patellar congruence angle were significantly correlated with the atrophy ratio of vastus medialis(coefficient=-5.76)and vastus lateralis(coefficient=8.35)during the follow-up period of 12 weeks.The alterations of lateral inclination angle were significantly correlated with the atrophy ratio of vastus medialis(coefficient=20.62),vastus lateralis(coefficient=-11.38)and rectus femoris(coefficient=-0.469)during the follow-up period 12 weeks.To sum up,ACL reconstruction can alleviate the dysfunction of patellofemoral joint to a certain extent.But,the unbalanced atrophy of quadriceps femoris once again destroyed the stability of patellofemoral joint following the operation,which might be one cause of patellofemoral joint pain and early onset of osteoarthritis after ACL reconstruction.So,rehabilitation training that focuses on quadriceps femoris especially the vastus medialis shortly following operation is suggested.

Acute Traumatic Primary Patella Dislocation in Children and Adolescents:A Detailed Evaluation of the Impact upon the Results

Background and Aim: Through accurate assessment of the risk factors and structural characteristics of children presenting with acute patella dislocation, this study aimed to evaluate the probability of recurrence and the effects on treatment. Materials and Methods: Demographic and radiological evaluation was made of each case. Contributory factors to patellofemoral instability were investigated. Surgical treatment was applied to 4 (15.39%) patients and conservative treatment to 22 (84.61%). Functional status before and after treatment was evaluated using the Kujala patellofemoral scoring system. Results: The patients comprised 8 (30.77%) males and 18 (69.23%) females with a mean age of 13.46 years. In 15 (57.69%) cases, there were patellofemoral complaints before the dislocation. The Kujala score was determined as mean 54.27 pre-treatment and 84.81 post-treatment in the conservative treatment group and mean 48.00 preoperatively and 75.25 postoperatively in the surgically treated group. No recurrence of patella dislocation was observed in any patient during the follow-up of both groups. Conclusions: Although it seems to be simple surgical intervention, as patella dislocation surgery can involve several complications, the surgical program must be very well planned and only applied to cases where necessary. With case-by-case assessment, the probability of recurrence of patella dislocation will be removed.

CT scanning and arthroscopic evaluation of patellofemoral malalignment

Objective To determine the pattern of malalignment and the extent of chondral damage, the patellofemoral joint was evaluated by CT scanning and the findings were proved by arthroscopic examination Methods In 20 cases, 40 knees were examined by CT scanning with and without quadriceps contraction in order to differentiate between static and dynamic abnormalities The CT images were analyzed The arthroscopic examination was carried out for 27 knees in 20 cases Results Ten knees had static patellar lateral subluxation and 16 knees dynamic lateral subluxation Eleven knees had static patellar lateral tilt, and 7 knees dynamic tilt All of the 27 knees showed arthroscopic patellar maltracking and chondral damage Conclusions The patellofemoral alignment, affection of quadriceps, and the extent of tight retinaculum may be precisely evaluated by CT measurement and proved by arthroscopic examination

Eccentric exercise in the prevention of patellofemoral pain in high-volume runners:A rationale for integration

Patellofemoral pain(PFP)is a common overuse condition seen in high-volume runners,such as military recruits.Exercise is commonly prescribed,with benefit,for the rehabilitation of individuals with PFP.However,a sub-stantial number of individuals with the condition do not achieve an optimal outcome,suggesting the condition can be difficult and complex.Given the challenging nature of the condition,and the risk of developing PFP in high-volume runners,it seems logical to investigate options for injury prevention.Eccentric exercise has been useful in the prevention of some pathologies so its utility in preventing PFP should be explored.Current evidence regarding prevention programs for PFP are limited.Preventative exercise programs for PFP have not been well described or reported,and questions remain regarding their effectiveness.Based on available evidence or lack thereof,and known physiological and clinical effects of eccentric exercise,suggestions for integration of eccentric exercise into PFP prevention programs are offered.Eccentric exercise may be useful for PFP prevention from a theoretical framework however additional longitudinal cohort studies would be useful in determining its utility.

Second-look arthroscopic evaluation of the articular cartilage after primary single-bundle and double-bundle anterior cruciate ligament reconstructions

Background Several reports have shown the progression of articular cartilage degeneration after anterior cruciate ligament （ACL） reconstruction. No report has been published about the cartilage comparing changes after single-bundle （SB） and double-bundle （DI3） ACL reconstructions. The purpose of this study was to evaluate the articular cartilage changes after SB and DB ACL reconstructions by second-look arthroscopy. Methods Ninety-nine patients who received arthroscopic ACL reconstruction were retrospectively reviewed at an average of 14 months after reconstruction, 58 patients underwent SB ACL reconstruction and 41 patients underwent DB ACL reconstruction. Hamstring tendon autografts were used in all patients. Second-look arthroscopy was done in conjunction with the tibial staple fixation removal at least one year after the initial ACL reconstruction. Arthroscopic evaluation and grading of the articular cartilage degeneration for all patients were performed at the initial ACL reconstruction, and at the second-look arthroscopy. Results The average cartilage degeneration at the patellofemoral joint （PFJ） was found significantly worsened after both SB and DB ACL reconstructions. This worsening were not seen at medial tibiofemoral joint （TFJ） and lateral TFJ. Grade II cartilage damage was the most common. At second-look arthroscopy, the average patellar cartilage degeneration was 1.14±0.14 （at first look 0.52±0.11） for the SB group, and 1.22±0.15 （at first look 0.56±0.12） for the DB group. The average trochlear cartilage degeneration was 1.05±0.16 （at fist look 0.10±0.06） and 0.66±0.17 （at fist look 0.17±0.09）, respectively. The average patellar cartilage degeneration showed no significant difference in both groups. However, the average trochlea cartilage degeneration in DB group was significantly less than in SB group. Conclusions Patellofemoral cartilage degeneration continued to aggravate after ACL reconstruction. DB ACL reconstruction could significantly decrease the trochlea cartilage degeneration compared with SB ACL reconstruction.

Painful locking of the knee due to bucket handle tear of mediopatellar plica

A case of swelling and anterior painful knee due to tear of mediopateUar plica is reported. The patient also felt clunk of the patellofemoral joint and knee locking. Under arthroscopic examination, a thick and fibrous plica was found medial to patellar, and a bucket tear along the plica from medial patellar retinaculum to infrapatellar fat pad. Polarized microscopic examination showed collagen fiber fragment and loss of light reflecting property. Neuroimmunohistology suggested up-regulation of synovial plica innervation in the area around the crack. This may be related to the pain. The bucket tear of mediopatellar plicacaused pain and lock of knee are more common than previously reported.