Acetabular loosening is often dangerous because the patient is pain free for several years. The following bone loss may represent the biggest challenge in revision surgery. Object of this study is to evaluate the use of an iliac stem cup (Link®) associated with impacted bone grafts in acetabular loosening and CDH. We performed 25 implants in loosening (13 grade 2 and 12 grade 3 of Paprosky): average age was 68 years old in 16 female and 9 male. Mean follow up was 22 months. We used bone grafts in 17 cases. In 1 case we cemented the Mcminn cup because of poor initial stability with no complication at 18 months. We noted radiolucency lines <
2 mm. in 1 case and bone resorption in 2 cases. The complications were: malpositioning of the stem (1%), sacroiliac pain (4%), superficial infection (2%) and DVT (1%). In conclusion, we can affirm that McMinn cup, despite a demanding surgical technique, represents a valid alternative to acetabular revision surgery because of the good initial stability, the respect of loading lines and besides it allows the use of pressurized bone chips.
Unicompartmental knee prosthesis (UKP) has been used for 40 years but it is still controversial. Nevertheless, this procedure is positive and it can be a good alternative if it is correctly indicated. From January 2001 we implanted 51 UKP in 47 patients. The diagnoses were: primary arthritis in 45 cases, post-traumatic degeneration in five and arthritis secondary to meniscectomy and ACL reconstruction in one. The mean age was 64.5 (range 49–81), 32 women and 15 men. Mean follow-up was 26 months (range 6–36). Post-operative recovery starts with physical rehabilitation, rarely with kinetics, and full weight-bearing walking the first day. DVT is prevented by treatment with low-molecular-weight heparin for 25 days and elastic stockings. From September 2002 we performed this procedure by minimally invasive surgery with an 8-cm incision and extramedullary intraoperative tools. We did not observe any infections or loosening: we performed just one revision of the femoral component because of a technical error. In four other cases a malpositioning of the femoral component was reported that was pain-free at follow-up. Current studies are starting to show valid and encouraging results at mid- and long-term follow-up, too. The best candidates for UKP are patients over 60 years who are not overweight, with asymptomatic patellar degeneration and no anterior instability and who perform light sport activity. In comparison with high tibial osteotomy (HTO), UKP shows some advantages, such as faster recovery and better mid-term results. In comparison with total knee arthroplasty (TKA), UKP gives better range of motion, faster postoperative recovery and an easier operation in case of infection or loosening. Some features should be evaluated and the surgical technique should employ state-of-the-art hardware. We evaluate the advantages of this procedure with particular emphasis on the minimally invasive technique. In conclusion, although our study is still in progress, correct patient selection, the surgical technique and the updated design of the new prosthesis can give satisfactory results and represent a valid alternative to HTO and TKA. In addition, compared to TKA, UKP shows a real economic advantage.
Acetabular loosening is often dangerous because the patient is pain free for several years. The subsequent bone loss may represent the greatest challenge in revision surgery. The extension of the bone loss may be small or wide, but it could also be associated with several defects. Usually, the most affected district is the dome, especially because the cup leans to migrate proximally. The object of this study is to evaluate the use of an iliac stem cup (Link®) associated with impacted bone grafts in acetabular loosening and congenital hip dysplasia (CDH). The surgical technique requires a posterolateral approach, dedicated cannulated hardware tools to improve iliac stem positioning, intraoperative C-arm and bone grafts to enhance primary stability. We performed 21 implants in 18 cases of acetabular loosening (10 grade 2 and 8 grade 3 according to Paprosky) and three CDH: average age was 68 years old in 14 women and seven men. Mean follow-up was 21 months. We used bone grafts in 17 cases. In one case we cemented the McMinn cup because of poor initial stability with no complications at 18 months. We noted radiolucency lines <
2 mm in one case and bone resorption in two cases. Mean Harris Hip Score (HHS) was 60 preoperatively and 88 postoperatively. The complications were: malpositioning of the stem (1%), sacroiliac pain (4%), superficial infection (2%) and DVT (1%). The primary cementless stability is achieved by the aid of an iliac palpator checked by fluoroscopy: the palpator works as a guide for the iliac stem to avoid malpositiong or wrong inclination. In addition, the dedicated cup trials could also function as an impactor for chips bone grafts in the so-called “impaction grafting technique”. In conclusion, we confirm that the McMinn cup, despite a demanding surgical technique, represents a valid alternative to acetabular revision surgery because of the good initial stability and the respect of loading lines and it also allows the use of pressurised bone chips. Furthermore, the hip centre is restored in acetabular loosening and CDH.