Posterior malleolar fractures are present in up to 44% of all ankle fractures. Those involving > 25% of the articular surface have a higher rate of posterior ankle instability which may predispose to post traumatic arthritis. The posterolateral approach to the distal tibia allows direct reduction and stabilization of the posterior malleolus and concomitant lateral malleolus fractures. An anatomical study was performed to establish the safe zone of proximal dissection to avoid injury to the peroneal vessels in this uncommon approach. 26 unpaired adult lower limbs were dissected using the posterolateral approach to the distal tibia as described by Tornetta et al. The peroneal artery was identified coursing through the intraosseous membrane on deep dissestion as the flexor hallucis longus muscle was reflected medially. The level of its bifurcation was also noted over the tibia. Perpendicular measurements were made from the tibial plafond to these variable anatomical locations.Introduction
Methods
Percutaneous plating of the distal tibia via a limited incision is an accepted technique of osteosynthesis for extra-articular and simple intra-articular distal tibia fractures. In this study we identify structures are risk during this approach. Thirteen unpaired adult lower limbs were used for this study. Thirteen, 16-hole synthes®LCP anterolateral distal tibial plates were percutaneously inserted according to the manufacturer instructions and confirmed by xray. Dissection was performed around the plate to examine the relation of nerves and soft tissue. The neurovascular bundle was under the plate in one case. Over the horizontal limb of the plate, typically the superficial peroneal nerve had a variable course over all four screw holes. The anterior tibial artery coursed over hole number 3 and the Extensor hallucis longistendon was positioned over hole 3 or 4. The Anterior tibialis tendon skirted hole 4 in 12 cases. Over the vertical limb of the plate, the neurovascular bundle coursed over holes, 5 to 7, the superficial peroneal nerve over holes 5 to 7.Method
Results
There are conflicting reports in the literature regarding the migration of femoral stems in revision hip arthroplasty following the use of impaction allografting with or without cement. In some cemented series distal migration of the prosthesis within the cement mantle has been recorded, as well as migration of the whole cement/prosthesis construct into the graft. The results of 26 cases of revision hip replacement using femoral impaction allografting in the absence of bone cement are reported. The mean follow up was 8.5 years (range 4 to 17 years). The technique employed a Freeman stem coated proximally with hydroxyapatite. Three cases required further revision at 2, 4 and 5 years for high subsidence and unacceptable thigh pain. The remaining 23 cases stabilised following a period of initial settlement and overall results have been comparable to other series that have utilised cement. The initial sinkage in this series occurred mainly in the first six postoperative months. These results, from a single surgeon series, demonstrate that the method is highly technique dependent and relies on adequate graft impaction.Introduction
Method and Results
An attempt to analyse whether impaction allografting without cement is more or less satisfactory than the technique with the addition of cement is compromised by conflicting reports of where the migration actually occurs. In some cemented series distal migration of the prosthesis within the cement mantle has been recorded as well as migration of the whole cement/prosthesis construct into the graft. Two prospective consecutive series of revision hip arthroplasties by a single surgeon:- Group 1; Uncemented impaction grafting revision hip replacement in a series of 30 patients (33 hips). Group 2; Cemented impaction grafting revision hip replacement in a series of 30 patients (31 hips). Group demographics were similar. Each case used the same design of hip implant with the only difference in design being a proximal hydroxyapatite coating used on the uncemented implants. Follow-up ranged from 2 to 17 years for the uncemented group and from 1 to 11 years for the cemented group. A validated hip scoring system was employed at regular follow up incorporating pain and functional assessment. Migration rates for the uncemented group were 0 to 15 mm for 30 hips; however 3 hips were revised early due to excessive migration. 3 hips sustained early complications (1 fracture, 1 dislocation, 1 varus malposition of stem). Migration rates for the cemented group were 0 to 9 mm for 29 hips, however the remaining 3 hips were revised due to excessive migration (up to 33mm). Although similar results were obtained in terms of success and also pain and function scores, marginal improvement in results did occur with the cemented series overall. Statistical significance was not reached however. More sinkage occurred in the uncemented group overall, the majority occurring in the first 6 post-operative months. Part of the improvement with the cemented series results may be explained by the improved techniques achieved whilst performing the uncemented series. These results from a single surgeon demonstrate that the method is highly technique dependent and relies on adequate graft impaction. With sufficient graft and an appropriate prosthetic design, cement is not essential to the early success of this method. However, the extent of the initial migration did not accurately predict a successful outcome for the procedure. The absence of cement removes any confusion as to the location of any migration.
Complications developed in seven patients: two implants failed requiring revision, one peri-prosthetic fracture occurred, one developed a flexion deformity of 25 degrees at the knee joint, which was subsequently overcome and three died of disseminated disease.
