ACL Update Hamstring vs Patellar Tendon - Sam Church 29/7/2004

Andy Williams 1993 (RNOH Talk)

Comparing the various ACL grafts is the subject of many papers and the consensus is that BPTB gives the best overall results.

Holmes et al 1991: 85% good results for BPTB at 5 years vs 50% semitendinosus.

Advantages of BPTB: stronger, easily available, ease of strong fixation, possible rapid healing at attachments because of bone plugs and surgery can be performed through the patella tendon window.

Disadvantages of BPTB: longer incision, patellar fracture, patellar pain (although all forms of ACL reconstruction are associated with this problem).

Advantages of hamstrings: less damage to knee extensor mechanism and relatively easy to harvest (?!).

Disadvantages of hamstrings: less strong (double strand), more elastic, permanent deformation once stretched (unlike BPTB), more difficult to fix to bone and take longer to attach to it, reduced hamstring torque (?recovers).

Sam Church 2000 (NWT Core Curriculum Talk)

Initial studies (Noyes 1984) showed 14mm BPTB to be 168% as strong as a normal ACL and 'all other grafts are weaker'. Faults were found in their methodology however and Woo et al found the true ACL to be much stronger.

Recent studies have shown that whilst a standard BPTB is 107% the strength of a normal ACL, a four-strand hamstring graft is actually is 229% as strong.

All mid-term results so far have compared two-strand hamstrings with BPTB.

Corry et al AJSM 1999: The only prospective study of BPTB vs four -strand hamstring (>80 in each arm). Short term results (2 years): no significant difference between the two groups for any measured variable (instability, pain, ROM, laxity etc).

So where are we now?¦..

Patellar vs Hamstring Tendons in Anterior Cruciate Ligament Reconstruction: A Meta-analysis.

Arthroscopy 17; 3 (March), 2001: 248-257

Yunes, Richmond , Engels & Pinczewski (New England, Boston , Sydney)

They start by stating that the current literature does not identify outcome differences between the two. Surgeons tend to stick to the method they prefer although some decide according to patient 'type'. Studies done so far to compare the two have used many different techniques (particularly with regard to fixation) and many have shown non-significant 'trends'. Hence they decided to do a meta-analysis.