Posterior cruciate ligament at total knee replacement

Abstract

e report the results of a prospective randomised trial which assessed the role of the posterior cruciate ligament (PCL) following total knee replacement (Genesis I; Smith and Nephew, Memphis, Tennessee). Over a four-year period, 211 patients underwent total knee replacement by the senior author (TJW). They were randomised at surgery to have the PCL either retained, excised or substituted with a posterior stabilised insert. If it was not possible to retain the ligament due to soft-tissue imbalance, it was released from its tibial insertion until suitable tension was obtained. This created a fourth group, those who were intended preoperatively to have the ligament retained, but in whom it was partially released as a result of findings at the time of surgery.All patients were evaluated using the Knee Society rating system (adapted from Insall). A total of 188 patients (212 knees) was available for follow-up at a mean of 3.5 years after surgery. Preoperatively, there was a varus deformity in 191 knees (90%) and a valgus deformity in 21 (10%).There were no statistical differences in the knee or function scores or the range of movement between the excised, retained and substituted groups. There were, however, significantly worse knee and function scores in the group in whom the PCL was released (p = 0.002).J Bone Joint Surg [Br] 2003;85-B:671-4.

A procedure‐specific systematic review and consensus recommendations for postoperative analgesia following total knee arthroplasty

“…One study also showed that the time to first analgesic request was significantly longer with parecoxib compared with placebo [14] (see Table 1). [19] Inconclusive Ropivacaine via femoral catheter [117] NS Bupivacaine via femoral catheter [35] NS Spinal diamorphine [42] NS Spinal morphine [43] NS Lumbar epidural ketamine [52] NS Lumbar epidural ropivacaine [50,53] Inconclusive Route and method of drug administration IV vs IM strong opioid [23] NS IV PCA vs IM strong opioid [24] IM superior for moderate pain scores Surgical approaches Medial trivector approach [61], Subvastus approach [62], vs parapatellar approach NS Posterior cruciate ligament (PCL) surgery during TKA: different surgical approaches [63] PCL released surgery inferior to other approaches Midvastus approach vs medial parapatellar approach [64] Midvastus superior at rest and on movement…”

“…Four studies were included that compared different surgical approaches for TKA surgery [61][62][63][64], but the results were inconclusive in terms of pain scores (see Table 2) given the limited number of studies for each technique.…”

PCL-retaining versus PCL-substituting TKR – Outcome assessment based on the “forgotten joint score”

“…PCL-retaining designs have been shown to be associated with a limited increase in the range of flexion (in comparison with PCL-substituting designs) in certain studies, [3][4][5][6] while no such increase in flexion has been found by others. [7][8][9] Studies which have found increase in flexion have attributed it to higher femoral roll back in PCL-retaining designs. The increased roll back is also said to increase the quadriceps lever arm and the power of extension.…”

An evaluation of the posterior cruciate ligament function in total knee arthroplasty with regard to its morphology and clinical properties

“…During surgery, unintended injury to the PCL often occurs by resection of the proximal tibia [17]. Additional PCL injuries can occur during an attempt to equalise flexion and flexion after resection of the articular ends of the bones forming the knee joint, which is a difficult technique [20]. If the PCL is too tensed, the flexion space is less than the extension space.…”