Background: Percutaneous adductor longus tenotomy (PAT) is a frequently used procedure, yet no study has ever compared its effectiveness and safety with those of open adductor longus tenotomy (OAT). We conducted this prospective study to describe the effects of PAT and to compare them with those of OAT.
Methods: This consisted of a cross-over randomized controlled trial including 50 consecutive hips from 27 patients with cerebral palsy scheduled for adductor tenotomy in the setting of multilevel tendon lengthening/release procedures or hip surgery (femoral or Dega osteotomy) in a university hospital. A pediatric orthopaedic surgeon conducted a PAT. Another surgeon extended the wound to explore what had been cut during the PAT, and completed the tenotomy if necessary. Hip abduction (HA) was assessed by a third surgeon immediately before PAT, after PAT, and then after OAT, using a goniometer, in a standardized reproducible manner. All 3 surgeons were blinded to the others' findings. Primary end-points included the percentage of tendon/muscle portion sectioned percutaneously, and the HA measure. Comparison between HA after PAT and OAT was done using a paired t-test with a 95% confidence interval. The influence of anatomic variants of adductor longus origin was also assessed.
Results: Mean HA (hips flexed) measured 40.36 degrees preoperatively and increased to 50.04 degrees after PAT (P<0.0001). After OAT, HA averaged 53.32 degrees with no statistical gain compared with that observed after PAT (P=0.2). The tendinous portion of adductor longus was cut to an average of 98% by PAT (completely in 46 cases and more than 75% in only 4 cases). The muscular portion of adductor longus origin was cut to an average of 83.7% (completely in only 15 cases, cut to more than 75% in 26 cases, and approximately 50% in 9 cases). The gain in HA positively correlated with the extent of the tendinous portion divided (P=0.03) but not with the extent of muscular portion divided. Results were independent of the anatomic variants of adductor longus origin. Partial section of adductor brevis after PAT was encountered in 6 cases. No major iatrogenic lesion was observed (obturator nerve, major vessels).
Conclusions: This is the only prospective study concerning the effects of PAT. The anatomic factor associated with gain in HA seems to be the extent of the section of the tendinous portion of adductor longus origin, which was found to be cut to more than 90% in all cases after PAT. The extent of muscular portion section does not seem to influence the gain in HA. The researchers detail the technique of percutaneous adductor tenotomy and show that when done correctly, PAT is a fast and simple procedure, as reliable and effective as the open release and without any major risks.
Level of evidence: Level II therapeutic study-prospective comparative study.