RESUMO
BACKGROUND: The principle of joint reconstruction surgery is to try to recreate the native joint biomechanics and stability. With respect to acromioclavicular joint (ACJ) surgery, much focus to date has been on restoring the superoinferior stability. There is concern that persistent horizontal instability following ACJ reconstruction could lead to poorer patient outcomes; therefore, we evaluated whether acromioclavicular (AC) ligament repair offers improved horizontal stability in conjunction with ACJ reconstruction. METHODS: A whole-body human cadaver was used. The ACJ was exposed and subjected to a constant 70N load on the lateral end of the clavicle to test the anteroposterior (AP), superoinferior (SI), and horizontal pivot angle (HPA) around the ACJ. The AC and coracoclavicular (CC) ligaments were subsequently divided, and the above three parameters were re-tested. Ligament augmentation and reconstruction system (Corin Group, Cirencester, UK), LockDown (LockDown Medical Limited, Redditch, UK), Endobutton (Smith and Nephew Inc., London, UK), and Neoligament implant (Xiros Ltd., Leeds, UK) were used to reconstruct the CC ligaments and tested with and without AC repair. RESULTS: The native ACJ allowed an average 2.48 mm AP and 3.88 mm SI translation with a 27° HPA. All synthetic implants significantly improved the vertical stability of the ACJ but allowed up to a four-fold increase in AP translation. Coupled with ACJ repair, all the reconstructions were far superior, especially in restoring horizontal stability. CONCLUSION: The implants varied in their approach to fixation and concentrated primarily on the reconstruction of CC ligaments. Our study was able to demonstrate that AC repair significantly improves the stability of the construct and significantly reduces vertical and horizontal instability.
RESUMO
AIMS: Talonavicular (TN) arthrodesis is a common procedure to treat arthritis of the TN joint.It can also form part of a wider triple fusion to restore the architecture of the foot.Traditional methods of arthrodesis are not universally successful. The aim of this study was to evaluate the clinical and radiological outcomes of those who had a TN fusion using the IOFiX system. Data was collected retrospectively from the hospital operation database. Inclusion criteria included patients who underwent a TN fusion between 2012 and 19 with the IOFiX system. All patients were over 16 years of age and at least one year post operation.Patient demographics were obtained, as well as rate of union and rate of re-operation for analysis. RESULTS: 35 patients were identified. The mean age was 58 years (range 34-85). The most common indication was osteoarthritis of the TN joint (n = 19), followed by acquired adult flat foot (n = 8), rheumatoid arthritis (n = 3), avascular necrosis (n = 2) and a previous nonunion.(n = 1). 9 % (n = 3) of patients did not achieve union by one year and 14 % (n = 5) required another operation subsequent to their initial surgery: four to remove metalwork, and one to treat non-union of the arthrodesis. The use of bone graft did not affect complication rates. TN fusion, when performed as part of a triple fusion, showed a tendency for reducing the rate of non-union, however this did not achieve statical significance. CONCLUSION: This study suggests that the IOFiX system offers a reliable and acceptable alternative technique for patients undergoing a TN fusion. Further work is required to assess if early signs of improved outcome when used in triple fusion, over isolated TN fusion,are significant.