Is lateral release plus medial plication with tibial tubercle osteotomy for medialization, and possibly trochlear plasty, an appropriate treatment for a patient with patella baja (inferior patellar position) and chronic lateral dislocation of the patella?

Assessment of Proposed Surgical Plan for Patella Baja with Chronic Lateral Dislocation

I do not agree with the proposed surgical plan as described, particularly the inclusion of lateral release, which is contraindicated in this clinical scenario and may worsen patellar instability.

Critical Problems with the Proposed Plan

Lateral Release is Contraindicated

• Lateral release should never be performed in chronic lateral patellar dislocation because it further destabilizes an already laterally displaced patella by releasing the remaining lateral restraints 1, 2, 3
• Lateral release is designed for patients with excessive lateral patellar tilt or tight lateral structures causing medial tracking problems, not for lateral instability 4, 3
• The proposed combination of lateral release with medial plication creates a fundamental contradiction—you cannot simultaneously weaken and strengthen opposing stabilizing structures for the same pathology 2

Patella Baja Complicates the Clinical Picture

• Patella baja (inferior patellar position) with associated necrosis represents a complex pathology that fundamentally alters normal patellofemoral mechanics 4
• The combination of patella baja and chronic lateral dislocation is unusual and suggests either prior trauma, prior surgery, or underlying structural abnormality requiring comprehensive imaging evaluation 5, 4
• MRI without IV contrast must be obtained to evaluate medial patellofemoral ligament integrity, cartilage injury extent, presence of loose bodies, and the degree of patellar necrosis before any surgical planning 5, 4

Appropriate Diagnostic Workup Required

Mandatory Imaging Studies

• Obtain knee radiographs including anteroposterior, lateral, and tangential patellar views to assess patellar height (Insall-Salvati ratio), trochlear morphology, and presence of osseous fragments 4, 6
• Order MRI without IV contrast to evaluate MPFL integrity, medial patellar retinaculum status, cartilage injury, and document the extent of patellar necrosis 5, 4
• Consider CT without IV contrast to evaluate patellofemoral anatomy, trochlear dysplasia (crossing sign, sulcus angle >145°), tibial tubercle-trochlear groove distance, and Q-angle 5, 4, 6

Critical Anatomic Factors to Document

• Measure Insall-Salvati ratio—patella alta (>1.2) is present in 86% of chronic lateral dislocators and significantly affects surgical planning 6
• Assess for trochlear dysplasia (present in 96% of chronic cases)—identified by positive crossing sign on lateral radiograph or sulcus angle >145° on axial view 6
• Document Q-angle—values >15° indicate genu valgum requiring correction before or concurrent with patellar stabilization 2, 7
• Evaluate for generalized ligamentous laxity, which predicts poorer outcomes with isolated soft tissue procedures 3

Evidence-Based Surgical Approach

Initial Conservative Management (Mandatory First Step)

• A structured 3-6 month trial of conservative management must be attempted first, as this successfully resolves symptoms in approximately 80% of patients with recurrent patellar instability 4
• Implement eccentric quadriceps exercises targeting vastus medialis obliquus as the cornerstone of treatment 4
• Surgery is justified only after documented failure of 3-6 months of properly executed conservative treatment 4

Appropriate Surgical Options if Conservative Treatment Fails

For chronic lateral dislocation with intact MPFL:

• Medial patellofemoral ligament repair/reattachment to femoral origin has a 46% redislocation rate in chronic cases with patella alta and trochlear dysplasia, making it inadequate as an isolated procedure 6

For chronic lateral dislocation with MPFL insufficiency:

• MPFL reconstruction (not repair) using autograft is the primary stabilizing procedure for chronic lateral patellar dislocation 1, 7
• Semitendinosus tendon transfer through transpatellar tunnel to reconstruct MPFL improves Kujala Index from 56 to 95 points at 13-month follow-up 7
• Extensive lateral release combined with MPFL reconstruction may be considered only in the rare scenario of fixed lateral dislocation with contracted lateral structures preventing passive medial reduction 1

Addressing patella alta (if I/S ratio >1.2):

• Tibial tubercle osteotomy for distalization (not medialization alone) is required when patella alta coexists with chronic lateral instability 6
• Medialization of tibial tubercle may be appropriate if increased tibial tubercle-trochlear groove distance is documented on CT 5

Addressing trochlear dysplasia:

• Trochleoplasty is a technically demanding procedure reserved for severe trochlear dysplasia (sulcus angle >145°) with recurrent instability despite MPFL reconstruction 6
• This should only be performed by surgeons with specific expertise in complex patellofemoral reconstruction 8

Specific Contraindications and Pitfalls

Absolute Contraindications to Lateral Release in This Case

• Chronic lateral patellar dislocation is an absolute contraindication to isolated lateral release 2, 3
• Lateral release without concurrent robust medial reconstruction will worsen lateral instability 1, 2

Critical Surgical Pitfalls to Avoid

• Never inject corticosteroids into patellar supporting structures, as this inhibits healing, reduces tensile strength, and predisposes to spontaneous rupture 4
• Do not proceed with complex reconstruction without documenting trochlear morphology, patellar height, tibial tubercle position, and MPFL integrity on advanced imaging 5, 4, 6
• Avoid MPFL repair (reattachment) in chronic cases with patella alta and trochlear dysplasia—reconstruction with autograft is required 6, 7
• Do not perform isolated soft tissue procedures when Q-angle exceeds 15° or valgus deformity exceeds 15°—bony realignment is necessary 2

Recommended Algorithmic Approach

Step 1: Complete diagnostic evaluation

• Obtain radiographs, MRI without contrast, and CT without contrast to document all anatomic abnormalities 5, 4

Step 2: Implement 3-6 month conservative trial

• Eccentric quadriceps strengthening, activity modification, topical NSAIDs 4

Step 3: If conservative treatment fails, surgical planning based on imaging:

• If MPFL insufficient + normal patellar height + normal trochlea: MPFL reconstruction alone 7
• If MPFL insufficient + patella alta (I/S >1.2): MPFL reconstruction + tibial tubercle distalization 6
• If MPFL insufficient + increased TT-TG distance: MPFL reconstruction + tibial tubercle medialization 5
• If severe trochlear dysplasia (sulcus angle >145°): Consider trochleoplasty only after MPFL reconstruction failure or in combination with MPFL reconstruction by experienced surgeon 6
• If fixed lateral dislocation preventing passive reduction: Extensive lateral release + MPFL reconstruction (this is the only scenario where lateral release is appropriate) 1

Step 4: Address patellar necrosis

• The presence of patellar necrosis may require staged procedures or alternative approaches including possible patellectomy in severe cases—this requires subspecialty consultation