The Oxford mobile bearing unicompartmental knee replacement (UKR) is a validated, highly successful implant with an excellent ten-year survivorship. From November 2001 to September 2006 three hundred and eighty two patients who had a medial cemented Oxford Unicompartmental knee replacement (Biomet, Bridgend, UK) via a minimally invasive approach were prospectively entered into a database and followed up as per departmental policy in the specialist joint assessment clinic. We have noted a minority of patients have persistent postoperative pain and/or mechanical symptoms resistant to the standard postoperative therapies. We report the outcome of 22 patients who had an arthroscopy for persistent pain and/or mechanical symptoms a median of 15 months (range 4 months – 31 months) following medial unicompartmental knee replacement. The median follow up time following arthroplasty was 38 months (range 16 months – 63 months). Post arthroscopy we divided our study patients into two groups; those who had an improvement in symptoms and those who had none. These groups were then compared, with particular reference to demographics, check radiographs and arthroscopic findings. The results showed that patients with anterior or anteromedial symptoms in whom a medial rim of scar tissue was identified and debrided sixty seven percent had a significantly increased probability of symptomatic improvement (p<0.005). In addition men appeared to significantly improve more that women (p<0.043). When performed this therapeutic intervention many prevent or at least defer the need for early revision to total knee replacement in some cases and we have no complications as a result of the arthroscopic intervention. This observational study provides evidence for a role for arthroscopy in selected patients with pain following unicompartmental knee replacement.
Recently biodegradable synthetic scaffolds (Trufit plug) have provided novel approach to the management of chondral and osteochondral lesions. The aim of this study was to assess our 2 year experience with the Trufit plug system. 22 patients aged 20 to 50 years old all presenting with knee pain over a 2 year period were diagnosed either by MRI or arthroscopically with an isolated chondral or osteochondral lesion and proceeded to either arthroscopic or mini arthrotomy Trufit plug implantation. In 5 patients plug implantation was undertaken along with ACL reconstruction (3), medial meniscal repair (1) and contralateral knee OCD screw fixation (1). Pre and post operative IKDC scores were obtained to assess change in knee symptoms and function. At a mean follow up of 15 months (range 2 – 24 months) improved IKDC scores were achieved with the scores improving with time. 2 patients have had a poor result and have had further surgery for their chondral lesions. One patient had failure of graft incorporation at second look arthroscopy and went onto to have a good result after ACI. The second patient had good graft incorporation on second look but had progression of osteoarthritic degeneration throughout the other compartments of the knee which were not initially identified at the time of Trufit plugging. We conclude that Trufit plug is an alternative method for managing isolated chondral and osteochondral lesions of the knee which avoids harvest site morbidity or the need for staged surgery.
