synonyms: MPFL reconstruction, Medial Patellofemoral Ligament Reconstruction
MPFL Reconstruction CPT
- 27420 (reconstruction of dislocating patella: Hauser type procedure)
- 27422 (reconstruction of dislocating patella; with extensor realignment and/or muscle advancement or release; Campbell, Goldwaite type procedure)
- 27424 (Reconstruction of dislocation patella; with patellectomy)
MPFL Reconstruction Anatomy
- see MPFL anatomy.
- Patellar stability is dependent on: bony constraint of the femoral trochlea; MPFL, medial retinaculum, and the vastus medialis. Any of these may be disrupted or dysplastic in patients with patellar instability. (Conlon T, JBJS 1993;75Am:682).
- >94% of patellar dislocations are related to MPFLrupture, generally from its femoral origin.
MPFL Reconstruction Indications
- Chronic / Recurrent patellar dislocation
- Acute dislocation with osteochondral injury
- Acute dislocation in high level athlete
- Patellar instability with trochlear dysplasia
MPFL Reconstruction Contraindications
- Patellar alta (consider concomitant distal transfer to the tibial tubercle)
MPFL Reconstruction Alternatives
- Extensor mechanism realignment
- Trochleoplasty (Verdonk R, Knee Surg Sports Traumtol Arthrosc. 2005;13:529).
- Anterior femoral osteotomy (Weiker G, Am J Knee Surg 1997;10:221).
MPFL Reconstruction Planning / Special Considerations
- Consider concomitant distal transfer of the tibial tubercle for patients with patellar alta.
- Through-tunnel tendon graft provides strongest MPFL reconstruction (Mountney J, JBJS 2005;87Br:36).
MPFL Reconstruction Technique
- Pre-operative antibiotics, +/- regional block
- General endotracheal anesthesia
- Supine position. All bony prominences well padded.
- Examination under anesthesia: ROM 0-130; varus laxity ext/30; valgus laxity ext/30; anterior drawer ER/IR, posterior drawer; lachman; pivot shift; ->10 degree increase in ER at 30° flexion, but not at 90 degrees. Patellar tilt, patellar subluxation.
- Tourniquet high on thigh.
- Prep and drape in standard sterile fashion.
- Perform routine knee arthroscopy. Repair any large osteochondral injuries to the patella if possible. Fixation may be provided with chondral darts or sutures through bone tunnels. Remove any small fragments, debride and microfracture.
- 3-4cm longitudinal incision midway between the patella and the medial epicondyle.
- Incise sartorius in line with its fibers.
- Identify inferior border of the Vastus medialis. The MPFL is just deep to the Vastus medialis.
- In acute situations locate the MPFL injury and repair +/- imbrication. It is most commonly avulsed from its medial epicondyle insertion which can be repaired with suture anchors.
- MPFL Reconstruction: Isometric location determined with a tensiometer. Graft tensioned at 60-90°. Graft options: quadriceps autograft, adductor magnus autograft, patellar tendon allograft, semitendinosis all/auto graft, tibialis anterior allograft etc. Fixation options include interference screws, Arthrex biotenodesis screws, Arthrex retrobutton in patella, suture anchors, etc.
- Close in layers.
MPFL Reconstruction Complications
- Continued instability, dislocation
- Anterior knee pain / kneeling pain
- Neurovascular injury (saphenous vein, saphenous nerve)
- Painful hardware
- Patellofemoral arthritis
- Patellar fracture
MPFL Reconstruction Follow-up care
- Post-Op: hinged-knee brace, ROM 0-60°, WBAT with crutches.
- 7-10 Days: wound check. Start ROM and quadriceps exercises with physical therapy.
- 6 Weeks: discontinue knee brace if quadriceps function and knee motion are normal.
- 3 Months: sport specific rehab.
- 6 Months: return to sport / full activities.
MPFL Reconstruction Outcomes
- 91.1% good/excellent results for MPFL reconstruction (Steiner TM, AJSM 2006;34:1254).
- 93% good/excellent result the hamstring autograft (Drez D, Arthroscopy 2001;17:298).
MPFL Reconstruction Review References