Table 2 Outcomes of hardware-free medial patellofemoral ligament reconstruction techniques
Study | Number of patients | Patients' characteristics | Follow-up | Surgical technique | Outcomes | Complications |
|---|---|---|---|---|---|---|
Abouelsoud et al. [27] Case series | 16 patients | Age: 8–15 (11.5) years Sex: 5 males and 11 females Pediatric patients with recurrent atraumatic patellar dislocation and generalized ligament laxity No patient had TT-TG distance more than 20 mm, or severe trochlear dysplasia | 24–34 (29.25) months | Single-bundle MPFL reconstruction using quadriceps tendon autograft Patellar fixation: the medial third of quadriceps tendon patellar attachment was preserved Femoral fixation: through stitches to the periosteum and bone in the MPFL femoral footprint and the adductor magnus tendon Graft tensioning: fixed at 30° of flexion before suturing Medial retinaculum plication was also performed | Kujala score: preoperatively 56 ± 4.72 points (range, 49–61) to postoperatively 94 ± 2.73 (range, 90–99), which is considered highly significant (P < 0.005) Mean Kujala score improvement: 38 No redislocation episodes were reported in any of the patients during the follow-up period | Flexion deficit: a patient (6.25%) reported losing the last 15° of flexion |
Lind et al. [18] RCT | 29 patients | Age: 18–46 (24.7) years Sex: 10 males and 19 females Patients with recurrent patellar instability with at least two lateral patellar dislocations and subjective instability symptoms with/without increased TT-TG distance or severe trochlear dysplasia | 2 years | Double-bundle MPFL reconstruction using a gracilis tendon autograft Patellar fixation: two bone tunnels in the proximal half Femoral fixation: the graft was looped around the adductor magnus tendon as femoral fixation Graft tensioning: lightly tensioned at 30° of flexion before suturing 10 mm tibial tuberosity medialization was performed in 20% of patients, in which tibial tuberosity trochlear groove distance (> 15 mm for men and > 20 mm for women) was increased. Patients with chondral pathology were treated with debridement alone. No patients had cartilage repair procedures | Kujala score: 75.8 ± 11.9 preoperatively to 89 ± 10 with no difference between groups (P = 0.73) Mean Kujala score improvement: 13.2 However, the soft-tissue fixation group was lower in age, had a higher preoperative Kujala score, and had a lower proportion of severe trochlear dysplasia There were no redislocations in either of the 2 study groups | Pain at the medial femoral condyle: three patients (11%) in both study groups. No patients had moderate or severe tenderness on palpation at the patella Flexion deficit: one patient (3.33%) in the screw fixation group Subjective patellar instability: one patient (3.45%) in the soft-tissue fixation group |
Maffulli et al. [33] Case series | 34 patients | Age: 13–39 (26.5) years Sex: 7 males and 27 females Recreational athletes with chronic recurrent patellar dislocations. Patients had at least two documented patellar dislocations requiring reduction under sedation without malalignment or trochlear dysplasia No patient had received a previous MPFL reconstruction, but four (11.77%) of them had undergone other soft-tissue procedures. Thirteen patients (38.24%) had ICRS grade IV patellofemoral osteochondral defects | 2–4.2 (3.5) years | Combined MPTL and MPFL reconstruction using a gracilis tendon autograft Tibial fixation: gracilis tendon distal attachment was preserved Patellar fixation: achieved through bone tunnels in the proximal and distal halves Femoral fixation: the graft was looped around the adductor magnus tendon Graft tensioning: established by manual 10 mm or one quadrant lateralization of the patella Osteochondral injuries were treated with debridement and/or microfractures | Kujala score: 47 ± 17 (range, 38–55) preoperatively to 82 ± 17 (range, 75–90; P = 0.02) postoperatively Mean Kujala score improvement: 35 No significant differences between patients with or without osteochondral lesions were found Three male patients (8.82%) had traumatic redislocation of the patella during sports activities | Drill-hole-related problems: 2 patients (5.88%) Hypoesthesia: 3 patients at 6-week follow-up. It persisted at final follow-up in one (2.94%) of them Anterior knee pain: 11 patients at 6-week follow-up persisted in 3 (8.82%) of them at final follow-up Osteoarthritis: 4 patients (11.76%) developed grade II osteoarthritis, and 3 (8.82%) developed grade III osteoarthritis |
Malecki et al. [34] Case series | 33 patients (39 knees) | Age: 8–18 (16) years Sex: 13 males and 20 females Patients with recurrent patellar dislocation Preoperatively, patellar tilt was observed in 25 knees and patellar shift in 32 knees. Twenty-one patients met the diagnostic criterion for ligamentous laxity (63.6%) | 2–3 (2.6) years | MPFL reconstruction with adductor magnus tendon autograft Patellar fixation: sutured through a single bone tunnel Femoral fixation: adductor magnus tendon distal attachment was preserved Graft tensioning: at 30° of flexion In 9 knees with patellar shift and lateralization of the tibial tuberosity, concomitant Roux-Goldthwait partial patellar medial transposition was performed. In 23 knees with patellar tilt, lateral retinacular release was also performed. Distal realignment was done when the Q angle was greater than 20° and when an additional patellar shift and an increased congruence angle were present | Kujala score: 66 points (range, 38–88) preoperatively to 92 points (range, 70–100) postoperatively Mean Kujala score improvement: 26 Four patients (10.26%) presented patellar redislocation after surgery, three cases during sports activities and one case during dancing. The recurrent events occurred in patients without partial transposition of the patellar tendon | Positive apprehension test: 7 cases (17.9%) at final follow-up |
Marot et al. [21] Multicenter longitudinal prospective comparative study | 29 patients | Age: (22.8) years Sex: 11 males and 18 females Patients with objective recurrent (minimum two episodes of dislocation) patellar instability, without malalignment or severe trochlear dysplasia | 2–5 years | Isolated quasi-anatomical double-bundle MPFL reconstruction using a minimum 180 mm length gracilis tendon autograft Patellar fixation: V-shaped tunnels in the proximal half Femoral fixation: the graft was looped around the adductor magnus tendon Graft tensioning: at 30° of flexion, allowing around 10 mm manual lateralization | Kujala score: 89.3 ± 8.5 postoperatively Mean Kujala score improvement: 27.3 ± 15.6 No statistical difference was found between the two groups Only one (3.45%) postoperative traumatic patellar dislocation occurred in the Isolated quasi-anatomical double-bundle MPFL reconstruction group at eight months postoperative during sports activities | Subjective patellar instability: two cases (3.51%) postoperatively, one in each group |
Monllau et al. [35] Case series | 35 patients (36 knees) | Age: (25.6 ± 9.4) years Sex: 17 males and 19 females Patients with objective recurrent patellar dislocations Twenty patients (55.6%) had increased TT-TG distance or patella alta | Minimum 27 (37.6) months | Quasi-anatomical double-bundle MPFL reconstruction with gracilis tendon autograft Patellar fixation: V-shaped bone tunnels in the superior third of the patellar medial border Femoral fixation: looped around adductor magnus tendon Graft tensioning: based on manual 10 mm lateralization at 30° of knee flexion An associated distal realignment procedure was performed in 20 patients (55.6%) | Kujala score: 63 (range, 49–70) preoperatively to 90 (range, 79–98) postoperatively (P < 0.001) Mean Kujala score improvement: 25 (range, 22–37) No patient experienced recurrent patellar dislocation in this series | Positive apprehension test: one patient (2.86%) Flexion deficit: two patients (5.8%), one of them required arthroscopic arthrolysis Hypertrophic wound scar: six knees (16.7%) No radiological progression of patellofemoral osteoarthritis was seen in any case at the final follow-up |
Shimizu et al. [36] Case series | 15 patients (20 knees) | Age: 11–41 (19.9) years Sex: 2 males and 13 females Patients with recurrent patellar dislocation Seven patients (35%) had patella alta, and six patients (30%) had osteochondral lesions | 60–215 (123) months | Double-bundle MPFL reconstruction using a semitendinosus tendon autograft Patellar fixation: through a single bone tunnel in the patella, only one side of the tendon graft was passed, and the other side was sutured to it on the anterior patellar surface Femoral fixation: to femoral attachment of the medial collateral ligament through a 1 cm slit Graft tensioning: lateral patellar edge and lateral trochlear margin position maintained congruent and tensioned at 30° of flexion Additional Insall's proximal realignment procedure was done. Six knees (30%) with severe osteochondral patellar lesions were treated with osteochondral fixation (three knees) and osteochondral transplantation (three knees) | Kujala score: significantly improved from 65.5 ± 17.0 preoperatively to 86.7 ± 14.9 postoperatively (P < 0.05) Mean Kujala score improvement: 21.2 No redislocation was observed. One patient had a history of subluxation postoperatively | Positive apprehensive sign: five knees (25%) Limited range of motion: one (5%) at two months postoperatively and improved to a full range of motion after manipulation under anesthesia. No limited range of motion was observed at final follow-up in any patient Osteoarthritis: five knees (25%) had osteoarthritic change postoperatively. Four of these five knees had a severe osteochondral lesion preoperatively, and osteochondral fixation or osteochondral transplantation surgery had been performed simultaneously |
Sobhy et al. [37] Case series | 29 patients | Age: 17–26 (20.1) years Sex: 21 males and 8 females All patients included in our study had recurrent patellar dislocations, with normal patellofemoral bone morphology and limb alignment, with no other ligamentous deficiencies Four patients (13.8%) had a positive family history of frank patellar dislocation. Each patient had suffered at least two episodes of patellar dislocation. Two patients had previous arthroscopic lateral retinacular release, and two patients had previous ACL reconstruction Nineteen cases had a traumatic event, while 10 had no history of trauma | 24–48 (32.2) months | Relay Technique: MPFL and TPFL reconstruction using semitendinosus tendon autograft Tibial fixation: semitendinosus distal attachment was preserved Patellar fixation: through bone tunnels Femoral fixation: achieved using a bone tunnel in the MPFL footprint. Graft and sutures were pulled in and tied in the opposite cortex Graft tensioning: tensioned in 20°–30° of flexion to approximately allow 5 mm of medial and lateral patellar glide | Kujala score: increased from 36.6 ± 6 (range, 22–48) preoperatively to 90.6 ± 7 (range, 78–100) postoperatively Kujala score values were significantly better in younger patients (P = 0.017) Mean Kujala score improvement: 54 No incidence of recurrence of patellar dislocation was detected in any case | Unstable feeling: 2 patients (6.9%). However, no positive apprehension or redislocation was found Flexion deficit: one patient (3.4%) reported a limited range of motion to 110° and inability to return to previous sports |