Acetabular revision for cavitary defects in failed total hip replacement remains a challenge for the orthopaedic surgeon. Bone graft with cemented or uncemented revision is the primary solution; however, there are cases where structural defects are too large. Cup cage constructs have been successful in treating these defects but they do have their problems with early loosening and metalwork failure. Recently, highly porous cups that incorporate metal augments have been developed to achieve greater intra-operative stability showing encouraging results. Retrospective analysis of twenty-six consecutive acetabular revisions with Trabecular Titanium cups. Inclusion criteria included aseptic cases, adult patients, end-stage disease with signs of loosening, no trauma nor peri-prosthetic fractures. Data was obtained for patient demographics, Paprosky classification, use of bone graft, use of acetabular augment, and Moore index of osseointegration.Introduction
Methods
Increased accuracy of pre-operative imaging in patient-specific instrumentation (PSI) can result in longer-term savings, and reduced accumulated dose of radiation by eliminating the need for post-operative imaging or revision surgery. The benefits and drawbacks of CT vs MRI for use in PSI is a source of ongoing debate. This study reviews all currently available evidence regarding accuracy of CT vs MRI for pre-operative imaging in PSI. The MEDLINE and EMBASE databases were searched between 1990 and 2013 to identify relevant studies. As most studies available focus on validation of a single technique rather than a direct comparison, the data from several clinical studies was assimilated to allow comparison of accuracy. Overall accuracy of each modality was calculated as proportion of outliers >3 % in the coronal plane.Introduction
Methods
Shoulder rotator cuff tears can be very debilitating and painful. Whilst massive tears may defy attempts at surgical repair due to the size of the defect, various biological materials have been proposed to reinforce tenuous repairs; initial results have been promising. It has been suggested that these materials may be used to bridge defects in the rotator cuff as a ‘patch’ or ‘interposition implant’ to provide pain relief and even offer some hope of functional recovery. A porcine dermal collagen implant (Permacol ©) has been engineered and introduced for the repair and reconstruction of soft tissues in the human body. In orthopaedics, it has been successfully used in the reinforcement and augmentation of rotator cuff repairs by suturing it over the repaired tendon. Proper et al reported good short term results in using this implant to bridge defects in massive rotator cuff tears and suggested it was good solution for this group of patients, reporting improvement in all aspects of the Constant Score. We have used Permacol © to reinforce cuff repairs with satisfactory results and thus considered its use as a salvage procedure to bridge massive rotator cuff defects, both of traumatic and degenerate origins. Unfortunately, we have seen with great concern that our results have been less than satisfactory. In a cohort of 20 patients who underwent Permacol © interposition / rotator cuff repair, 4 of these have failed, despite a promising initial recovery phase with good pain relief. We believe that use of this and similar implants to bridge a defect in the cuff is not indicated; MRI and dynamic ultrasound examination showed an inflammatory response in the shoulder, and resulting weakness/failure of the implant. We present clinical, radiographic, and histological findings of our experience and a discussion as to the probable cause for the failure of this implant in this particular group of patients.
