Not the most robust joint in the body, it can sublux anteriorly or posteriorly. Anterior subluxations can be caused by an inversion injury of the ankle while the posterior subluxation is often cumulative due to over-flattening of the foot.

Often posttraumatic subluxations of this joint mimic lateral ligament injuries of the knee or lateral meniscus tears. Sometimes the varus stress test will be painful as the lateral ligament attaches to the fibular head.

Anatomy and Biomechanics

The superior tibiofibular joint is a modified ovoid synovial joint that works in concert with the inferior joint. The combination of both joints forms a functional modified sellar with one degree of freedom, pronation and supination. Pronation occurs when the tibia and fibular rotate medially causing the two bones to cross each other. At the superior joint the fibular glides superoposteromedial. Supination is the opposite.

Examination Findings

The posterior subluxation is characterized by a reduction of the anterolateral glide and the anterior subluxation by a reduced posteromedial glide.

Technique

Anterior Subluxation
The anterior subluxation is reduced by a posterior manipulation. The patient is laid supine with the leg rotated inwards to bring the anterolateral-posteromedial joint line vertical. The medial aspect of the knee is supported with a sandbag to prevent a valgus stress being induced during the manipulation. The therapist stabilizes the tibia with the medial hand and places the pisiform area of the other hand over the anterior aspect of the fibular head and thrusts directly downwards into the bed.

Posterior Subluxation
The posterior subluxation is pushed forwards. The patient is set up in four point kneeling with the affected leg a little more extended at the hip. The therapist stands on the opposite side to the affected leg. This brings the manipulating hand in line with the joint line. The therapist stabilizes the leg with the caudal hand and places the pisiform area of the other hand over the posterior aspect of the fibular head. The fibular is thrust downwards and laterally.