Adolescent idiopathic scoliosis: a prospective randomised trial protocol comparing clinical and radiological outcomes in minimally invasive surgery versus standard posterior spinal fusion in a single-centre, the Rizzoli Orthopaedic Institute, Bologna, Italy.

INTRODUCTION: Minimally invasive spine surgery (MISS) has been shown to be safe and effective in adolescent idiopathic scoliosis (AIS) correction, even though there is no consensus on which treatment provides the best results. METHODS AND ANALYSIS: The present study will be a randomised controlled trial with allocation 1:1. We will enrol 126 patients with Cobb≤70° undergoing AIS surgery. Patients will be divided into two groups, according to a randomisation list unknown to the surgeons. Group 1 will be treated with posterior spine fusion and group 2 with MISS. MISS technique: two midline noncontiguous skin incisions of 3 cm in length, 3-4 segments (6-8 pedicles screws) instrumented per skin incision, uniplanar and polyaxial pedicle screws inserted bilaterally on each side of the proximal and distal levels, rod translation manoeuvre and C-D manoeuvre performed on the distal part. Clinical and radiological follow-ups will be performed for 5 years. Values of Cobb angles degrees will be collected to study the correction rate of the structural major curve. Postoperative and preoperative anterior-posterior (AP) direct radiography will be compared with the last follow-up examination. Operative time, preoperative haemoglobin (Hb) and second postoperative day Hb, full length of hospitalisation, time to achieve verticalisation and time to remove the drainage will be recorded. Numeric Rating Scale (NRS) medium score will be assessed immediately after surgery and during the whole postoperative rehabilitation treatment to estimate pain reduction. Complications will be collected postoperatively and throughout the whole follow-up period.Moreover, questionnaires will be administered at follow-up (NRS, Scoliosis Research Society-22 and Oswestry Disability Index) for the clinical assessment. ETHICS AND DISSEMINATION: The study protocol has been approved by the local ethic committee Area Vasta Emilia Romagna Centro. Written informed consent will be collected for all the participants. Findings of this study will be disseminated through peer-reviewed publications and conference presentations. TRIAL REGISTRATION NUMBER: NCT05860673.

Minimally invasive surgery versus standard posterior approach in the treatment of adolescent idiopathic scoliosis: a 2-year follow-up retrospective study.

PURPOSE: This is a monocentric retrospective controlled study that compares the safety and efficacy of posterior minimally invasive surgery (MISS) to standard posterior spinal fusion (PSF) surgery in adolescent idiopathic scoliosis (AIS). METHODS: We retrospectively collected 111 patients with Lenke type 1-6 AIS who were treated with MIS (n = 47) or PSF (n = 64) between February 2019 and January 2021 with a 2-year clinical and radiological follow-up. MIS technique was applied via two midline noncontiguous skin incisions ranging from 3 to 7 cm in length, so we obtained the arthrodesis only in the exposed tract, passing the rods below the fascia, avoiding the complete muscular sparing. Values of Cobb angles degrees were collected to study the correction rate of the structural major curve. Postoperative AP direct radiography and preoperative AP direct radiography were compared with the last follow-up examination. Operative time, preoperative hemoglobin (Hb) and second postoperative day Hb, full length of hospitalization, time to achieve verticalization and time to remove the drainage were recorded. NRS medium score was assessed immediately after surgery and during the whole postoperative rehabilitation treatment to estimate pain reduction. Complications were collected postoperatively and throughout the whole follow-up period. RESULTS: There was no significant difference between the two groups in terms of radiographic and clinical features. The correction rates of the structural curve resulted to be not significantly different between MISS and PSF (64.6 ± 11.7 vs 60.9 ± 13.2, p = 0.1292) as well as for the correction rate of the secondary curve between the two compared techniques (59.1 ± 13.2 vs 59.2 ± 12.4, p = 0.9865). The two groups had comparable operative time (210 min vs 215 min). The MIS group had a significantly lower reduction of postoperative Hb in comparison with PSF group (2.8 ± 1.3 mg/dl vs 4.3 ± 1.5 mg/dl, p < 0.0001). The postoperative NRS score was lower in MIS group (1.9 ± 0.8 vs 3.3 ± 1.3). PSF group was observed to have a significantly longer period of hospitalization than MIS (5.2 ± 1.4 days vs 6.3 ± 2.9 days, p = 0.206). Complications were more frequent in PSF group rather than in MFS group. CONCLUSIONS: MISS is a safe and capable alternative to PSF for AIS patients with curves < 70°, with analogue capacity of scoliosis correction and same operative time and with advantages in blood loss, length of stay and postoperative pain.

Weight bearing versus conventional CT for the measurement of patellar alignment and stability in patients after surgical treatment for patellar recurrent dislocation.

PURPOSE: To compare weight-bearing cone-beam computer tomography (CBCT) and conventional computer tomography (CT)-based measurements of patellofemoral alignment and stability in patients surgically treated for recurrent patellar dislocation. These scans implied respectively single-leg up-right posture, the knee flexed, and lower limb muscles activation, versus supine position with the knee extended. METHODS: A total of 17 patients (11 males/6 females) after surgical reconstruction with fascia lata allograft for recurrent patellofemoral dislocation were analyzed at 60-month follow-up. Tilt and congruence angles and tibial tuberosity-trochlear groove (TT-TG) offset were measured on images obtained from CBCT and conventional CT scans by three independent and expert radiologists. Paired t tests were performed to compare measurements obtained from the two scans. Inter-rater reliability was assessed using a two-way mixed-effects model intra-class correlation coefficient (ICC). RESULTS: Only TT-TG offset was found significantly smaller (p < 0.001) in CBCT (mean 9.9 ± 5.3 mm) than in conventional CT (mean 15.9 ± 4.9 mm) scans. ICC for tilt and congruence angles and for TT-TG offset ranged between 0.80-0.94 with measurements in CBCT scans, between 0.52 and0.78 in conventional CT. CONCLUSION: In patients surgically treated for recurrent patellar dislocation, TT-TG offset was found overestimated with conventional CT. All measurements of patellofemoral stability and alignment were found more consistent when obtained with weight-bearing CBCT compared to conventional CT.

Good results are reported at 60-month follow-up after medial patello-femoral ligament reconstruction with fascia lata allograft for recurrent patellar dislocation.

PURPOSE: The aim of this study was to evaluate the efficacy of a new minimally invasive surgical technique for the reconstruction of the medial patellofemoral ligament (MPFL) with fascia lata allograft at 60-month minimum follow-up. METHODS: Nineteen consecutive patients with chronic recurrent patellar dislocation were treated with MPFL reconstruction (53% isolate procedure, 47% in combination with other treatments). Seventeen patients (11 males/6 females) were available at 60-month follow-up and were clinically evaluated with validated scores. New episodes of patellar dislocation were considered failures. Radiographic and CT scan evaluation were executed preoperatively and at 60-month follow-up. RESULTS: All clinical scores improved from preoperative assessment to 24-month and 60-month follow-up (p < 0.001). Kujala score increased from 61.2 ± 18.1 to 86.7 ± 8.7 and 82.1 ± 10.2; KOOS increased from 54.5 ± 19 to 86.8 ± 9.6 and 84.3 ± 7.6; VAS for pain decreased from 5.1 ± 2.2 to 2.4 ± 1.5 and 1.7 ± 1.2; Tegner score increased from 3 [2-4] to 5 [3-8] and 5 [3-9], respectively. Objective IKDC improved too. No significant improvements between the 24-month and 60-month follow-up evaluations were recorded. Anterior knee pain was reported in two patients (12%). Treatment failure, a new episode of patellar dislocation 25 months after the surgery, was observed in one patient (6%). Radiographic OA changes were not statistically significant between preop and 60-month follow-up. Tuberosity-troclear groove (TT-TG) distance and the patellar tilt angle were subjected to significant changes due to MPFL reconstruction and associated procedures. CONCLUSION: MPFL reconstruction with fascia lata allograft, alone or combined with other procedures, is a reliable treatment option for recurrent patellar dislocation with a success rate of 94% and without cartilage deterioration at 60-month follow-up. LEVEL OF EVIDENCE: IV.