The aim of this study was to assess the results of combined arthroscopically assisted posterior cruciate ligament reconstruction and open reconstruction of the posterolateral corner in patients with chronic (3 months or more) symptomatic instability and pain. A retrospective analysis of all the patients who had a combined reconstruction of the posterior cruciate ligament and the posterolateral corner between 1996 and 2003 was carried out. Nineteen patients who had the combined reconstruction were identified from the database. All the patients were assessed pre- and post-operatively by physical examination and three different ligament rating scores. All the patients also had weight bearing radiographs, MRI scans and an examination under anaesthesia and arthroscopy pre-operatively. The PCL reconstruction was performed using an arthroscopically assisted single anterolateral bundle technique and the posterolateral corner structures were reconstructed using an open Larson type of tenodesis.Objective
Patients & methods
Early stabilisation after an anterior cruciate ligament (ACL) rupture reduces future meniscal injury. We may therefore expect protection of articular cartilage from ACL reconstruction, but this has yet to be shown. Our aim wasto determine the effect of meniscal injury on the long term risk of osteoarthritis (OA) following ACL reconstruction using Single Photon Emission Computed Tomography (SPECT, a 3 dimensional radionuclide scan). We studied a prospective series of 31 patients (mean age at injury of 29 years) who had bone-patellar tendon-bone ACL reconstruction for unstable, ACL deficient knees. Mean follow-up was 10 years (range 9-13). Patients were separated into two groups according to the status of their menisci at the time of ACL reconstruction, those with intact menisci in group 1 (n=15) and those who required partial meniscectomy in group 2 (n=16). The contra-lateral normal knee was used as a control. All knees were clinically stable with high clinical scores (mean Lysholm score 93 and mean Tegner activity score 6). In group 1 (intact menisci) only one patient (7%) had clinical symptoms of OA and was the only patient with increased uptake on SPECT compatible with early OA. In group 2 (partial meniscectomy), two had clinical symptoms of osteoarthritis, and five patients (32%) had increased uptake on SPECT compatible with early OA. None of the control knees had early OA on SPECT. The prevalence of OA 10 years post ACL reconstruction, using the most sensitive investigation available, is very low in patients who had intact menisci (7%), but increases 5 fold (32%) if a meniscal tear was present. We recommend early ACL reconstruction to preserve the menisci to minimise the long term risk of OA.
Retrieval study:
14 knee replacement components were retrieved after revision procedures. The average surface roughness (Ra) of the articulating regions of each condyle was measured by surface profilometry and compared to Ra of non-articulating regions, which acted as controls on each implant. In vitro testing:
Pin-on-plate testing of 6 paired CoCr pins and vacuum γ-irradiated UHMWPE discs was carried out under a force of 2.3kN at 1Hz to investigate how the articular Ra of CoCr pins varied with increasing number of cycles. Ra was measured at 0, 10, 100 and 1000 cycles using surface profilometry.
Retrieval analysis:
Average medial femoral condyle Ra was significantly greater than control Ra (p=0.040). Average lateral femoral condyle Ra was not significantly greater than control Ra (p=0.158). Significantly higher average Ra was seen on the medial condyles when compared with the lateral condyles (p <
0.05). 8/14 retrieved femoral components had ≥1 significantly roughened condyle (p<
0.05). In vitro testing:
At 100 and 1000 cycles the Ra of the CoCr pins was significantly greater than Ra at 0 cycles (p<
0.05).
Reconstruction was done by a standard 4-strand hamstring technique using an endobutton proximally and a spiked washer and screw distally in the tibia. The IKDC, Lysholm and Tegner scores were used to assess the knees pre and post-operatively. Stability was measured using the KT-1000 arthrometer.
The incidence of osteoarthritis (OA) after an ACL reconstruction is not clear. Reports estimate between 12% and 61% at 8 years post ACL reconstruction. Single Photon emission Computed Tomography (SPECT) scanning (a 3 dimensional radionuclide bone scan) is a sensitive and quantitative method of assessing knee OA, with abnormalities appearing before plain xray and arthroscopic changes.