Relationship between bony tunnel and knee function in patients after patellar dislocation triple surgeries—a CT-based study

Abstract

We aimed to assess the CT-based bony tunnel valuations and their correlation with knee function after patellar dislocation triple surgeries. A retrospective study was performed on 66 patients (70 knees) who underwent patellar dislocation triple surgeries. The surgery was MPFL reconstruction primarily, combined with lateral retinaculum release and tibial tubercle osteotomy. CT examinations were performed to determine the femoral tunnel position, along with the patellar and femoral tunnel width 3 days and more than 1 year after operation for follow-up. Functional evaluation based on Kujala and Lysholm scores was also implemented. We compared tunnel width of the first and last examinations and correlated femoral tunnel position of the last examination with knee function. At the last follow-up, femoral tunnel position in the anterior-posterior direction was moderately correlated with knee function. Femoral tunnel position in the proximal-distal direction was not associated with postoperative knee function. Patellar and femoral tunnel width increased significantly at the last follow-up. However, no significant functional difference was found between patients with and without femoral tunnel enlargement. Our results suggested that the tunnel malposition in anterior-posterior position based on CT was related to impaired knee function during the follow-ups.

Does medial patellofemoral ligament reconstruction result in femoral tunnel enlargement? A systematic review

“…Three studies utilized bioabsorbable screws [ 10 , 17 , 18 ]. Qin et al used both titanium and bioabsorbable screws [ 19 ], whereas type of screw used was not reported in three studies [ 11 , 12 , 20 ]. Of the 365 patients identified, 212 had recurrent patellar dislocation (more than two previous episodes).…”

“…Neri et al did not report degree of FTE [ 11 ], whereas Kita et al reported association between FTE and potential risk factors without reporting values for these [ 20 ]. The case series by Qin et al [ 19 ] and Wong et al [ 18 ] carried some concerns regarding their risk bias due to their retrospective nature and being performed in a single center. Only one non-randomised comparative study was identified [ 10 ].…”

“…Berard et al [ 10 ] and Schüttler et al [ 17 ] diagnosed FTE when the femoral tunnel’s original surface area increased to twice its original size. Kita et al [ 20 ] and Neri et al [ 11 ] measured percentage increase in femoral tunnel area from baseline, while Qin et al [ 19 ] and Wong et al [ 18 ] reported absolute increase in femoral tunnel surface area. Rates of FTE ranged from 38.7 to 77.1%.…”

“…Of the five studies reporting on the consequences of FTE, four reported that this did not lead to negative clinical outcomes [ 10 , 12 , 19 , 20 ]. Schüttler et al [ 17 ] reported better outcomes in patients with FTE, whereas Neri et al [ 11 ] observed FTE predicted lower functional scores.…”

Correlation Analysis between Tibial Tuberosity‐Trochlear Groove Distance and Other Patellar Stability Parameters in Young and Middle‐aged Populations

“… 13 Theoretically, the abnormal TT‐TG distance of the Chinese population being shorter than the critical value reported in the literature is due to the different sizes and shapes of the bones and muscles of knee joints. Although few studies have focused on the TT‐TG distance in Chinese subjects, 14 , 15 more clinical data are needed to verify the differences in TT‐TG distance between Chinese and foreign populations due to bias and limitations in measurement methods. Furthermore, the exact mechanism of patellofemoral instability has not been clearly clarified.…”