1. Two year results of MPFL reconstruction using a strip of Quadricepstendon
B. Obada, Al. Serban, M. Zekra, T. Bajenescu, Crina Alecu
Emergency Clinical Hospital of Constanta, Romania
P400
Objectives
Reconstruction of the MPFL for the treatment of patella instability has achieved increased attention over the last years. The majority of operative techniques utilize hamstring grafts within bone tunnels or anchors at the patella. Despite good clinical results complications, such as implant breackage, patella fractures through bone tunnels and loss of knee motion have been experienced. Therefore, we describe the two year clinic results of an alternative minimal invasive MPFL reconstruction technique using a trip of quadriceps tendon (QT).
Patients & Methods
Twenty-three consecutive patients (10 male, 13 female; mean age 22,9 years ± 4.2) undergoing isolated MPFL reconstruction for patellofemoral instability have been included in the prospective study. All patients were evaluated clinically, radiologically and with subjective questionnaires (VAS, Tegner-, Lysholm-, Kujala Score) pre-operative and 6, 12 and 24 months post-operative.
Operative technique. A 10 to 12mm wide, 3mm thick and 8 to 10 cm long strip from the central aspect of quadriceps tendon was harvested subcutaneously. The tendon strip was then dissected distally on the patella, left attached, divergent 90° medially underneath the medial prepatellar tissue and fixed with 2 sutures. In the distal end of the graft resorbable pull-in sutures were placed in a web-stitch technique. A soft tissue tunnel is created between layer II and III and the graft is then pulled through and fixed in a 6 to 7mm bone tunnel on the femur in 20° of knee flexion with a bioabsorbable interference screw.
Results
Two patients had a positive apprehension test at 12 and 24 month. There was no re-dislocation during the follow-up period and no additional operative procedure due to complications had to be performed.
VAS Pain
Pre-OP 6m
12m
24m
Mean (SD)
3,2 (±2,8)
1,4 (±1,7)
1,1 (±1,6)
0,9 (±1,5)
Lysholm
12m
24m
Mean (SD)
88,1 (±12,0)
88,8 (±9,6)
Kujala
12m
24m
Mean (SD)
89,2 (±7,9)
93,3 (±5,4)
Tegner
12m
24m
Mean (SD)
5,4 (±2,0)
5,5 (±1,9)
Fig.1 Step 1 of graft harvest. A double knife of 10 or 12 mm is pushed proximally 8 to 10 cm above the superior patellar border.
Fig.2 Step 2 of graft harvest. A tendon separator (3mm) is pushed proximally 8 to 10 cm above the superior patellar border.
Fig.4 The tendon strip is left attached on the patella on 1 side and the free end is augmented with resorbable 2-0 sutures by use of a baseball stich technique.
Fig.3 Step 3 of graft harvest. The quadriceps tendon strip is cut at the desired length (8 to 10 cm) with a tendon cutter.
Fig.5 The quadriceps tendon strip is detached from the bony surface of patella.
Fig.6 From the medial patellar border, the prepatellar tissue is elevated creating a tunnel. The graft is passed through the tunnel and secured to the tissue on medial patellar border with 2-0 sutures.
Conclusions
MPFL reconstruction with a strip of QT harvested in a minimal invasive technique was found to be associated with a good short term clinical results. We think that this technique presents a valuable alternative to common hamstring technique for primary MPFL reconstruction as well as for MPFL revision surgery.