Outcomes of femoral de-rotation osteotomy for treatment of femoroacetabular impingement in adults with decreased femoral anteversion

Abstract

Decreased femoral anteversion is an often overlooked factor in femoroacetabular impingement (FAI), with potential to exacerbate both cam and pincer type impingement, or itself be the primary cause. Femoral de-rotation osteotomy (FDO) is a surgical option for symptomatic patients with such underlying bony deformity. This study aimed to investigate outcomes of FDO for management of symptomatic FAI in the presence of decreased (<5°) femoral anteversion. Secondary aims were to describe the surgical technique and assess complications. This study included 33 cases (29 patients) with average pre-operative anteversion measuring –3.1° (true retroversion). At an average follow-up of 1.5 years (19.8 months), 97% reported significant improvement. The overall average post-operative International Hip Outcome Tool (iHOT-33) score of 70.6 points (r: 23–98) compared to the average pre-operative score of 42.8 points (r: 0–56) for the 11 patients with available pre-operative scores suggests an overall improvement. The minimal clinically important difference for the iHOT-33 is 6.1 points. Patients with both pre- and post-operative iHOT-33 scores available demonstrated a statistically and clinically significant improvement of 37.7 (r: 13–70) points. There were three cases (9%) of delayed union and two cases (6%) of non-union early in the series which prompted evolution of the technique. Locking screw removal was performed in 33% of patients for a resultant overall re-operation rate of 45%. The findings suggest improvement in patient-reported outcomes can be achieved with FDO for symptomatic FAI in the setting of decreased femoral anteversion (<5°).

Patellofemoral joint load and knee abduction/adduction moment are sensitive to variations in femoral version and individual muscle forces

“…Most patients presenting with a pathologic version are ultimately treated surgically, with derotational osteotomy being the procedure of choice to correct the angle and alleviate further manifestation 4,33–40 . This procedure involves transecting the femur at some point along the shaft and rotating to the surgeon's estimate of the angle needed to correct the pathology.…”

“…Most patients presenting with a pathologic version are ultimately treated surgically, with derotational osteotomy being the procedure of choice to correct the angle and alleviate further manifestation. 4,[33][34][35][36][37][38][39][40] This procedure involves transecting the femur at some point along the shaft and rotating to the surgeon's estimate of the angle needed to correct the pathology. Preoperative imaging establishes the subject-specific starting angle (i.e., 40°) and the known physiologic range gives the surgeon a target end angle (12−20°, for a total rotation of 20−28°), but no standardized system exists for determining this target end angle.…”

Less in-toeing after femoral derotation osteotomy in adult patients with increased femoral version and posterior hip impingement compared to patients with femoral retroversion

“…The effect of decreased FV or femoral retroversion is discussed controversially because others reported similar outcomes (compared to FAI patients with normal FV) [ 18 ]. Recently, treatment with femoral osteotomy using intramedullary nailing with improved short-term outcomes were reported [ 19 ].…”

Coxa valga and antetorta increases differences among different femoral version measurements

“…Although indications are still evolving, femoral derotational osteotomies are increasingly performed in the setting of FAI and DDH to correct for femoral version abnormalities and improve biomechanics. [5][6][7][8][9][10] Consequently, the exact quantification of femoral version is crucial for diagnosis and surgical planning. Several methods for measuring femoral version have been described.…”