Clinical results after treatment for bidirectional patellar subluxation: Minimum 2-years follow-up.
BACKGROUND
We describe the preliminary clinical results of a patellar stabilization technique to treat bidirectional patellar subluxation (BPS).


METHODS
Patients: six patients (one male, five females; mean age 30.2years) underwent this procedure with a minimum of 24months follow-up. Patients were assessed for clinical instability, patellar complications, and need for revision surgery. Patient functional outcomes were evaluated using the criteria of Crosby and Insall and the Kujala Anterior Knee Pain Scale at the time of final follow-up. Patient satisfaction was assessed using a subjective questionnaire.


METHODS
A semitendinosus tendon autograft is coursed through a transverse tunnel in the distal quadriceps tendon. The medial and lateral aspects of the graft are passed from the quadriceps tendon within subfascial tunnels to the MPFL attachment site and lateral epicondyle, respectively. The graft is fixed in 60° of knee flexion with suture anchors.


RESULTS
Surgery for recurrent instability was performed in one case. There were no cases of infection, quadriceps tendon rupture, or patella fracture. At average follow-up of 29.2months (range, 24 to 38months), outcomes were good to excellent in 4/6 of cases. Kujala scores improved significantly from 33.3 (range, three to 58) preoperatively to 70.8 (range, 39 to 96) postoperatively (p<0.05). 5/6 patients reported being satisfied to completely satisfied with their result.


CONCLUSIONS
Patients undergoing bidirectional patellar stabilization with a single tendon graft showed improved postoperative functional scores. The technique is successful in reducing pain and restoring bidirectional patellar stability at 2-years follow-up.


METHODS
IV, retrospective case series.
Department of Orthopaedic Surgery, McLaren Orthopedic Hospital, 2727 S. Pennsylvania Ave., Lansing, MI 48910, USA.
Michael
M
Saper
Department of Orthopaedic Surgery, McLaren Orthopedic Hospital, 2727 S. Pennsylvania Ave., Lansing, MI 48910, USA.
Candice
C
Brady
Department of Orthopaedic Surgery, McLaren Orthopedic Hospital, 2727 S. Pennsylvania Ave., Lansing, MI 48910, USA.
Robert
R
Zondervan
Department of Orthopaedic Surgery, McLaren Orthopedic Hospital, 2727 S. Pennsylvania Ave., Lansing, MI 48910, USA; Mid-Michigan Orthopaedic Institute, 830 W. Lake Lansing Rd #190, East Lansing, MI 48823, USA. Electronic address: f27david@aol.com.
David
D
Shneider
D000328:Adult; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D008875:Middle Aged; D031222:Patellar Dislocation / Q000601:surgery*; D017060:Patient Satisfaction; D020127:Recovery of Function; D013997:Time Factors; D016896:Treatment Outcome; D055815:Young Adult
Bidirectional subluxation; Knee; LPFL; MPFL; Patellar instability