Patellofemoral Pain William R. Beach, M.D. Raymond Y. Whitehead, M.D.

Anatomy and Biomechanics Arthicular surface –2-facets with a central ridge Passive stabilizers –Patellar tendon –Lateral retinaculum –Medial patellofemoral ligament Static checkrein Resist lateral translation Dynamic stabilizers –Quadriceps muscle

History Pain –Character –Location –Onset –Intensity –Exacerbation –Remittance Effusion Trauma –Subluxation –Dislocation

History Previous treatment Other joint involvement (gout, R.A.) Litigation Worker’s compensation Psychological components

Physical Examination Alignment –Varus/valgus –Rotational Q-angle –Norms – male(10º) and female(15º) –Flexion angle Tubercle-sulcus angle Extensor mechanism –Patellar alta vs. baja Hamstring tightness

Physical Examination Patellofemoral crepitus Patellar tracking –J-sign –Apprehension Lateral retinaculum –Tenderness –Tilt –Patellar mobility Quad strength –IT band friction synd. –Pes anserinus bursitis

Radiographic Evaluation AP, lateral and axial –Varus/valgus alignment –Accessory ossification centers –Osteochondral fractures –Patellar relationship Alta Baja

Radiographic Evaluation Merchant axial –45 deg and 30 caudal tilt –Normal patella – no tilt or subluxation beyond deg of flexion

Radiographic Evaluation Sulcus angle –Angle formed by the trochlear ridges –Mean - 138º mediallateral

Radiographic Evaluation Congruence angle –Angle formed by bisecting the sulcus angle and central patellar ridge –Mean = -6º +/- 6º (central ridge should lie medial to the bisector) mediallateral

Radiographic Evaluation Subluxation – central patellar ridge is lateral to the bisector of the sulcus angle Tilt – patella centered in the trochlea but the medial facet is elevated away from the trochlea

Radiographic Evaluation Lateral patellofemoral angle Line parallel to the lateral facet and a line drawn across the posterior femoral condyles Angle formed will normally be open laterally (>8º) If open medially suggest patellar tilt

Computed Tomography Precise midpatellar transverse images parallel to both femoral condyles Images at 15, 30 and 45 degrees of flexion Normal standing alignment – maintain rotational and angular alignment Normal patellar tracking = patella centered in the trochlea without tilt at 15º of flexion Visually the easiest way to determine tilt and subluxation

Computed Tomography Patellar tilt angle –angle between line along lateral facet of the patella and line along posterior condyles –normal > 12 º

Computed Tomography – 0°

Computed Tomography – 15°

Computed Tomography – 30°

Computed Tomography – 45°

Computed Tomography – 60°

Magnetic Resonance Imaging Less helpful than CT Assess bone and cartilage lesions

Bone Scan Occult fracture Painful bipartite patella Increased uptake with patellar tendonitis Avoid electrocautery for revision release

Conservative Treatment Goal – reduce symptoms, improve quad strength and endurance Short arc quads – reduce patellofemoral load and friction Quad stretching Hamstring stretching Pelvic tilt – stretch hip extensors and abductors

Conservative Treatment Patellar mobility exercises – lateral retinaculum stretching Aerobic conditioning NSAIDS Bracing/McConnell taping –Patellar cut-out brace –J-pad

Surgical Treatment Arthroscopy –Lateral release –VMO Plication Tibial tubercleplasty –Elmslie-Trillat – medial –Maquet – anterior –Fulkerson – anterior/medial –Roux-Goldthwaite – open growth plate Patellectomy

Arthroscopy and Lateral Release +/- Arthroscopic VMO Plication Debridement of the articular surface Result of patellar malalignment/maltracking Lateral release for isolated patellar tilt Lateral release alone is insufficient for subluxation

Arthroscopy and Lateral Release +/- Arthroscopic VMO Plication Technique –Lateral release from muscle to the anterolateral portal Avoid the lateral portion of the quad tendon Electocautery for primary release

Arthroscopic VMO Plication Technique –Arthroscope in the lateral portal –Thru and thru #2 panacryl suture on a large curved needle –Sutures from 2 – 4 o’clock –Small incision to tie the sutures –Flex the knee to 90º to assure proper suture placement

Tibial Tubercleplasty Indication –Elmslie-Trillat – for subluxation without arthrosis –Maquet – for primary athrosis –Fulkerson – for subluxation and arthrosis Best for patellar lesion, distal lateral facet Medialization realigns extensor mechanism Anteriorization unloads the articular cartilage Lateral release should always be performed

Fulkerson Anteromedial Tibial Tubercle Transfer

Patellectomy –Last resort –Extensive articular damage of the patella and unremitting pain –Patella must have satisfactory alignment