[Anatomical double bundle reconstruction of medial patellofemoral ligament with allograft tendon in the treatment of patellar dislocations].
OBJECTIVE
To investigate the clinical therapeutic results of allograft tendon for anatomical reconstruction of medial patellofemoral ligament (MPFL) for the treatment of patellar dislocations.


METHODS
From September 2008 to June 2013, 16 patients with patellar dislocation underwent MPFL reconstructions. There were 2 males and 14 females, aged 11 to 27 years old (16 years old on average). Patellar dislocations occurred in 11 left and 5 right knees. The disease course ranged from 3 to 10 years. The frequency of dislocation ranged from 9 to 33 times (19 times on average). Affected knee joints showed patellar instability; the range of action for patella obviously increased. The X-ray films showed patellar dislocation. The preoperative Q angle was (36 ± 9)°, and the congruence angle was (63 ± 18)°. Reconstruction was performed via allograft tendon. Allograft tendon was fixed through the superomedial pole of the patella, and the other end was fixed at the natural MPFL insertion site near the medial femoral condyle with an interference screw in a bone tunnel. All the patients were evaluated postoperatively; Kujala patellofemoral scores, objective knee function, complications, and reoperations were assessed.


RESULTS
Primary healing was achieved in all cases. No infection or necrosis and absorption of grafts was observed. All the patients were followed up for an average of 16.4 months (ranged, 10 to 24 months) postoperatively. At the latest follow-up, all the patients had no pain, swelling and patellar instability; neither patella redislocation nor fracture occurred. The X-ray films showed good position of tunnel 6 months after operation, and the congruence angle was (5 ± 9)°, showing statistically significant difference when compared with preoperation (P < 0.05). The postoperative Q angle was (17 ± 8)°, the Kujala knee function score improved significantly from 45.20 ± 9.20 to 89.30 ± 6.40 at the latest follow-up, showing statistically significant difference (P < 0.05).


CONCLUSIONS
MPFL reconstruction improves clinical symptoms. Anatomical MPFL reconstruction is effective for patellar dislocation, and it offers good recovery of the premorbid patella mechanics. The interference screw provides firm fixation. Allograft can avoid the graft harvest site morbidity, but it increases the cost of the surgery.
Hui
H
Tang
Yong-Qing
YQ
Xu
Tian-E
TE
Zheng
Yong
Y
Sha
Xiao-Shan
XS
Xu
Wan-Qiu
WQ
Zhao
Yong
Y
Cui
Xi-Jiao
XJ
Zhang
Shao-Quan
SQ
Pu
Li Chuan
Chun-Xiao
CX
Li
D000293:Adolescent; D000328:Adult; D064591:Allografts; D002648:Child; D005260:Female; D006801:Humans; D008023:Ligaments, Articular / Q000601:surgery*; D008297:Male; D031222:Patellar Dislocation / Q000601:surgery*; D057071:Patellofemoral Joint / Q000601:surgery*; D019651:Plastic Surgery Procedures / Q000379:methods*; D013710:Tendons / Q000637:transplantation*