Knee joint osteoarthritis was significantly more common at 5 years after anterior cruciate ligament reconstruction in patients with patellar tendon autografts than in those with hamstring tendon autografts.
Dr. Matjaz Sajovic, along with researchers from the General Hospital Celje and the University of Ljubljana (Slovenia), conducted a prospective controlled study in which 64 patients with anterior cruciate ligament (ACL) rupture were randomized to reconstruction with hamstring tendon autografts (32) or patellar tendon autografts (32).
The comparative success of the two procedures and their associated incidence of early knee joint osteoarthritis were compared 5 years after surgery.
Among the 54 patients (85%) available for clinical and radiographic follow-up, there were no significant differences in graft rupture or contralateral ACL rupture in the 28 with hamstring tendon grafts and the 26 with patellar tendon grafts. Returns to preinjury activity levels were similar in the hamstring tendon group, 23 of 28, and in the patellar tendon group, 23 of 26. Among those with hamstring tendon autografts, grafts ruptured in two patients and contralateral ACLs ruptured in two. In those with patellar tendon autografts, grafts ruptured in two and contralateral ACLs ruptured in three (Am. J. Sports Med. 2006;34:1933–40).
Clinical and subjective test results were similar for the two groups; however, osteoarthritic changes significantly differed. Radiographic grade B knee joint osteoarthritis was present at the 5-year follow-up in 13 of the 26 patients (50%) with patellar tendon autografts and in 5 of the 28 patients (17%) with hamstring tendon autografts.
In other studies, osteoarthritis rates have been higher after meniscal resection. The authors attribute the lower rate in their study to significantly more (P = 0.027) subtotal meniscal resections performed in the hamstring tendon group, 12 of 28 patients, compared with the patellar tendon group, 4 of 26.
Further, medial meniscal injury was noted at reconstruction in 12 of 28 with hamstring tendon autografts and in 12 of 26 with patellar tendon autografts. Lateral meniscal injury was noted in six patients in each group. “It is difficult to obtain patients with solitary ACL tears without any other intra-articular lesions,” the investigators said.
At 5-year follow-up, radiographic evidence of knee joint osteoarthritis was significantly elevated in patients from the patellar tendon group (P = 0.012). This finding “emphasizes the hypothesis that the choice of the graft is crucial in the development of degenerative knee joint disease at 5 years after ACL reconstruction.”
Only one previous prospective, long-term study has compared the two autografts, but the findings excluded all patients with more than one-third meniscectomy and atraumatic graft failure. After 7 years, patellar tendon grafts were associated (P = 0.002) with more osteoarthritis (Am. J. Sports Med. 2005;33:1337–45).