MPFL-Rekonstruktion mit autologer Gracilissehne bei Patellaluxation: MPFL-reconstruction with autologous gracilis tendon graft for patella dislocation

Patellofemoral instability, respectively dislocation of the patella is reported with an incidence of 7-49/100000 and causes 2-3 per cent of all knee injuries. More than 10 per cent of all musculoskeletal symptoms are caused by patellofemoral instability. The etiology of patella dislocation is multifactorial, common risk factors are a dysplastic trochlea, patella alta, increased patella tilt and TTTG-distance as well as the condition of the medial patellofemoral ligament. Depending on individual symptoms and risk factors therapy can be held conservatively or operatively. Multiple techniques with different approaches and outcomes have been described. With the evaluated technique the medial patellofemoral ligament is reconstructed with an autologous graft (Gracilis-tendon) and anatomically inserted at the patellar site by a soft tissue fixation without further implants. This prospective follow-up aims to examine postoperative development of function, stability and pain of the injured knee as well as the patient’s subjective evaluation of their condition. Between January 2011 and November 2012 27 patients between 12 and 45 years of age who underwent surgical reconstruction due to recurrent dislocation of the patella were included in the study following the before stated inclusion criteria. The follow up was 12 months. Besides the “Kujala Anterior Knee Pain Score” and “Flandry-Score” a standardized clinical examination was performed. Of the 27 included patients we were able to follow up 24 patients over 12 months, 3 patients dropped out after 6 months postoperatively. Results of “Kujala Anterior Knee Pain Score” improved from 72 points (IQR=35) to 95 points (IQR=9.25) after 12 months with a highly significant improvement after 6 months already. Results of “Flandry-Score” improved from 65.7 points (IQR=29.5) to 89.9 points (IQR=7.75) after 12 months with again a highly significant improvement after 6 months already. Postoperatively the most often stated problems were squatting and kneeling. No further limitations of ADL were reported after 6 months. Intensity and frequency of pain caused by the operated knee was decreasing after 6 months. No problems with sporting activities were reported after 6 months, the quadriceps muscle showed atrophy in 51.9 per cent after 12 months though. Already after 3 months no giving way was reported. Within the 27 examined patients one traumatic re-dislocation occurred. No further complications could be found. Subjective evaluation of the patient’s health condition improved highly significant after 6 months compared to the preoperatively reported state. Reconstruction of the medial patellofemoral ligament with autologous gracilis graft and soft tissue fixation showed very good results concerning re-dislocations and stability after one year. Rehabilitation and resumption of sporting activities proceeded quickly. The reported results are promising, still further studies with higher numbers of patients and longer follow up are will be needed