The sulcus deepening trochleoplasty—the Lyon’s procedure

Abstract

Sulcus deepening trochleoplasty is a technically demanding procedure with precise indications: high grade trochlear dysplasia with patellar instability and/or abnormal tracking. The main goal is to decrease the prominence of the trochlea and to create a new groove with normal depth, thus optimising patellar tracking. Associated abnormalities should be specifically treated. Recurrence of instability is very rare after this procedure and is more likely to result from missed associated abnormalities. Although results seem very good in terms of instability, further evidence is still needed since the groups of patients in the published series are heterogeneous. Trochleoplasty is not indicated for patellofemoral arthritis or pain. As any surgical procedure, sulcus deepening trochleoplasty is liable to complications.

The lateral condyle index: a new index for assessing the length of the lateral articular trochlea as predisposing factor for patellar instability

“…In addition, we found no pathological MR signs for abnormal patella height or TT-TG distance [14,15], which would merit specific surgical considerations [12,18]. Therefore, another underlying pathomorphology other than those described by Dejour et al [2,12] must be present for proximal lateral patellar subluxation close to extension. The documented (too) short lateral articular trochlea quantified by the lateral condyle index could be a relevant factor for lateral patellar instability.…”

“…Special attention was given to the signs of trochlear dysplasia described by Dejour et al [2,9,12], such as crossing sign, supratrochlear spur and double contour.…”

“…To date, trochlear dysplasia has been defined as a flat, articular zone of variable length, which is situated proximally and is associated with a shallow groove distally [2]. Dejour et al [2,9,12] described four types of trochlear dysplasia (A-D) based on true lateral radiographs in which the trochlea has only a shallow (<4 mm) or no groove, or even a trochlear bump (anterior translation of the trochlear floor). However, the proximal extent of the cartilaginous lateral, central and medial trochlea has never been described.…”

“…Trochlear dysplasia is considered to be one of the most relevant factors of patellar instability [2,5,[7][8][9][10][11][12]. To date, trochlear dysplasia has been defined as a flat, articular zone of variable length, which is situated proximally and is associated with a shallow groove distally [2].…”

The incidence of trochlear dysplasia in anterior cruciate ligament tears

“…Trochlear dysplasia has been directly associated with both recurrent patellar dislocation [18][19][20] and AKP [21,22] in patients with patellar instability, since it has been observed in 96 % of patients with PF disorders and in only 3 % of controls [15,22]. The surgical correction of trochlear dysplasia is done with the sulcusdeepening trochleoplasty procedure, in which the elevated groove is eliminated and the abnormal sulcus is deepened [23][24][25]; this can also rarely be enriched by the addition of patellar osteotomy in order to achieve a better congruency between the two articulating bones [26]. Some authors have also suggested that trochlear dysplasia may extend more distally to the intercondylar notch and therefore could be more frequent in patients with ACL tears due to a reduced intercondylar notch size that predisposes to ACL injury (Fig.…”