Bilateral double osteotomy in severe torsional malalignment syndrome: 16 years follow-up

Torsional malalignment syndrome (TMS) is a well defined condition consisting of a combination of femoral antetorsion and tibial lateral torsion. The axis of knee motion is medially rotated. This may lead to patellofemoral malalignment with an increased Q angle and chondromalacia, patellar subluxation and dislocation. Conservative management is recommended in all but the most rare and severest cases. In these cases deformity correction requires osteotomies at two levels per limb.

From 1987 to 2002 in our institution three patients underwent double femoral and tibial osteotomy for TMS bilateral correction (12 osteotomies). All patients were reviewed at mean follow-up of 16 years.

At final follow-up no patients reported persistence of knee or hip pain. At clinical examination both lower limbs showed a normal axis and a normal patella anterior position. Pre-operative femoral version measurement showed an average hip internal rotation of 81.5° (range 80°-85°) and average hip external rotation of 27.2° (10°-40°). Thigh-foot angle measurement showed an average value of 38.6° (32°-45°). At final follow-up femoral version measurement showed an average hip internal rotation of 49° (range 45°-55°) and average hip internal rotation of 44.3° (20°-48°) (Figs. 1, 2, 3, 4, 5, 6). Thigh-foot angles measurement showed an average value of 21.6° (18°-24°) outward.

We recommend a clinical, radiographical and CT scan evaluation of all torsional deformity. In cases of significant deformity, internally rotating the tibia alone is not sufficient. Ipsilateral outward femoral and inward tibial osteotomies are our current recommendation for TMS, both performed at the same surgical setting.