Tissue sparing hip replacements have recently gained popularity, in an attempt to provide shorter hospital stay, faster recovery time and potentially to reduce morbidity and complications. Direct anterior approaches (DAA) have been shown to allow faster recovery, but also appear to be associated with a higher incidence of complications, especially during the learning curve. Mini-posterior approaches have the advantage of increased familiarity, however may not be maximally muscle sparing. Prospective and retrospective data was collected following a published protocol. This included patient demographic data, theatre time, units of blood transfused, length of stay, functional scores and radiological parameters. Rates of conversion to posterior approach and complications were also documented. The results of our first 100 cases completed are presented: Within this initial cohort, three patients suffered major complications: These included an anterior dislocation, which was successfully reduced with closed reduction under general anaesthetic, an early (day 6) periprosthetic fracture, which was successfully revised to a cemented prosthesis, and a case of stem subsidence. Our results also suggest a learning curve effect, limited to theatre time and blood loss. Complications were evenly distributed throughout the period of study and are of similar frequency to standard approaches. As the first European centre to adopt the SuperPATH approach, we have shown that the published results from America can be reproduced. In contrast to DAA, the learning curve is not associated with higher rates of femoral fracture and other complications. The fact that the approach is extensile, being the superior part of the posterior approach, allows for all of the advantages of muscle preservation with the safety of potential extension when necessary.
The risk of dislocation in large diameter metal on metal hip replacement is significantly lower than in standard THR. This is due to the increased primary arc, increased jump distance and possibly a suction effect. Our unit has performed over 1500 of these cases with an overall revision rate of <1%. We report a case series of dislocations in 5 large diameter metal on metal hips undertaken at our unit. All cases were reduced closed and investigated for cause of dislocation. Radiological investigation included plain film radiographs and CT to exclude component mal-position and MRI to document soft tissue deficiency. Metal ion levels were measured and microbiological investigation was undertaken.INTRODUCTION
METHOD
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.
Operation data is now entered onto the database by the surgeon or co-ordinator at the time of surgery. Thereafter, the database automatically produces annual Oxford Hip Questionnaires, EQ-5D questionnaires and invite letters to patients for clinical review at stipulated time-points. Questionnaires are returned by patients and scanned. This data is then electronically imported to the database without transcription error. Patients attend special Outcome clinics, staffed by Research Fellows and SpR’s, who examine the relevant hip and review their radiographs. The findings are recorded and the paper forms scanned and imported into the database. Non-responders are identified from the database and are chased up via telephone by the coordinator. Data is extracted from the database with queries and presented using database reports.