Surgical treatment for recurrent patellar dislocation with severe torsional deformities: Double-level derotational osteotomy may not have a clear advantage over single-level derotational osteotomy in improving clinical and radiological outcomes.

PURPOSE: The purpose of this study was to investigate whether double-level (femur + tibia) derotational osteotomy is superior to single-level femoral derotational osteotomy for recurrent patellar dislocation with severe femoral and tibial rotational deformities (femoral anteversion >30° and external tibial torsion >30°). METHODS: Between January 2015 and June 2020, a total of 115 knees with recurrent patellar dislocation treated with combined medial patellofemoral ligament reconstruction (MPFL-R) and derotational osteotomies were evaluated after a minimum follow-up of 2 years. Among these cases, 15 knees that underwent double-level derotational osteotomy were included in the double-level group, which was propensity-matched in a 1:2 ratio to a single-level group of patients who underwent single-level femoral derotational osteotomy (30 knees). The clinical and radiological outcomes were evaluated and compared between the groups. Furthermore, the foot progression angle was measured preoperatively and 2 years after surgery. RESULTS: The patient-specific variables did not differ significantly between the double- and the single-level groups after propensity score matching. The postoperative mean foot progression angle was significantly lower in the double-level group than in the single-level group (9° ± 8° vs. 15° ± 11°; p = 0.014); however, there were no statistically significant differences between the groups in terms of any other clinical and radiological assessments. CONCLUSION: For patients with severe femoral and tibial torsional deformities (femoral anteversion >30° and external tibial torsion >30°), the double-level derotational osteotomy is superior to single-level osteotomy in maintaining normal foot progression angle, but it does not show an advantage in terms of patient-reported outcomes, radiological results and redislocation rate at minimum 2 years of follow-up. Furthermore, concomitant excessive external tibial torsion (>30°) did not have an adverse effect on clinical outcomes in patients who underwent derotational distal femoral osteotomy with MPFL-R due to excessive femoral anteversion. LEVEL OF EVIDENCE: Level III.

Miserable malalignment syndrome associated knee pain: a case for infra-tubercle tibial de-rotation osteotomy using an external fixator.

INTRODUCTION: Miserable malalignment syndrome is a complex torsional lower limb deformity with limited consensus on surgical treatment. We present the outcome of de-rotation of the tibia alone using an external fixator. METHODS: Fifteen patients (22 segments) were operated on between 2012 and 2020; 13 presented with anterior knee pain, and two presented with out-toeing. Gait analysis was done in nine patients, and CT scan rotational profile, including tibial tubercle-trochlear groove distance, femoral version, and tibial torsion, were calculated. Kujala knee pain score and visual analogue pain score (VAS) were recorded. All underwent infra-tubercular osteotomy of the tibia and midshaft osteotmy of the fibula and application of a hexapod circular frame to gradually internally rotate the tibia until the foot aligned with the patella. RESULTS: There was no preoperative clinical or radiographic evidence for patellar instability, femoral anteversion 30° (21°-54°), and external tibial torsion 50° (37-70). The mean age at surgery was 21 years (12-37) with a mean follow-up of 20 months (9-83). All osteotomies healed, and the frames were removed at a mean of 111 days (80-168). The mean VAS score improved from 8(5-9) to 1(0-4) postoperatively (P < 0.001). The mean Kujala knee pain score increased from 53 (30-75) to 92 (54-100) postoperatively (P < 0.001). The mean preoperative foot progression angle (FPA) was 37° (20°-50°), with 13 postoperatively walking with neutral FPA. One patient walked with symmetrical + 10° and the other with - 5° FPA. All patients reported relief of knee pain and were satisfied with the alignment. CONCLUSION: Gradual correction of severe external tibia torsion with a hexapod external fixator and an infra-tubercle tibial osteotomy could provide an optimum method to eliminate knee pain and improve limb alignment in miserable malalignment syndrome.

Equation predicting tibial-tuberosity to trochlear-groove distance following supratubercle osteotomy: Radiographic proof of concept.

BACKGROUND: Supratubercle tibial rotational osteotomies are useful in patellar stabilizing procedures with high tibial-tuberosity to trochlear-groove distance caused by excessive external tibial torsion. An investigation determined one degree of internal tibial rotation results in 0.68 mm reduction of tibial-tuberosity to trochlear-groove distance, but did not account for anatomical variability. METHODS: This is a radiographic proof of concept for equation validation. We compared two different derived equations, a complex four-variable and simplified two-variable equation, to the literature relationship and true measured value from CT imaging. Bilateral pre-operative CTs of 37 patients, evaluated for malalignment, were reviewed retrospectively. We virtually simulated derotations of five, ten and fifteen degrees, and compared the reduction in tibial-tuberosity to trochlear-groove distance measured radiologically from CTs to the one predicted by our equation. FINDINGS: The difference between the true change in tibial-tuberosity to trochlear-groove distance and that obtained using our four-variable was statistically insignificant for all derotation angles (p > 0.05), and the two-variable equation it was statistically insignificant for five and fifteen degrees of derotation (p > 0.05). Conversely, the true values were statistically different from those found using the published relationship (p < 0.05 for all). INTERPRETATION: This new equation accounts for individual patient anatomy, for a more accurate relationship between internal rotation of the distal segment of the tibia and the subsequent decrease in the tibial-tuberosity to trochlear-groove distance. The change was overestimated using the linear relationship, which may result in under correction. Future studies will assess true post-operative distance change following osteotomy.

Supra tubercular tibial osteotomy and gradual correction with Taylor spatial frame for the management of Torsional malalignment syndrome - surgical technique and outcomes.

BACKGROUND: Surgical management of Torsional Malalignment Syndrome (TMS) traditionally consists of simultaneous correction of both femoral anteversion and external tibial torsion. We hypothesise that a single supra tubercular osteotomy followed by tibial derotation with Taylor Spatial Frame (TSF) is sufficient to provide significant improvement in both appearance and function. METHOD: This is a retrospective single surgeon case series performed at a tertiary referral centre in the UK. Data collected included patient demographics, clinical findings and CT rotational profile measurements. All patients completed pre and post-operative Oxford Knee Score (OKS) and Kujala Anterior Knee Pain Scale (AKPS) functional outcome scores for analysis. RESULTS: There were 16 osteotomies in 11 patients with complete data sets for analysis performed between 2006 and 2017. Mean age of 16.7 ± 0.8 years. The results show significant improvements in post-operative functional assessment scores, with mean OKS increasing by 18.3 and mean AKPS increasing by 31.4. Average pre-operative thigh-foot angle (TFA) was 44.7°, this was reduced to 12.8° post-operatively, representing an average correction of 31.9°. CONCLUSION: The results show that supra tubercular osteotomy, followed by gradual correction with TSF, can be used to provide a significant improvement in both appearance and function for patients suffering from TMS.

Patient specific instrumentation allow precise derotational correction of femoral and tibial torsional deformities.

BACKGROUND: Rotational malalignment deformities of the lower limb in adults mostly arise from excessive femoral anteversion and/or excessive external tibial torsion. The aim of this study was to assess the correction accuracy of a patient specific cutting guides (PSCG) used in tibial and femoral correction for lower-limb torsional deformities. METHODS: Forty knees (32 patients) were included prospectively. All patients had patellofemoral pain or instability with torsional malalignment for which a proximal tibial (HTO) or distal femoral (DFO) or a double-level osteotomy (DLO) had been performed. Accuracy of the correction between the planned and the postoperative angular values including femoral anteversion, tibial torsion, coronal and sagittal alignment were assessed after tibial and/or femoral osteotomy. RESULTS: Forty knees were included in this study. In cases of HTO, the correction accuracy obtained with PSCG was 1.3 ± 1.1° for tibial torsion (axial plane), 0.8 ± 0.7° for MPTA (coronal plane) and 0.8 ± 0.6° for PPTA (sagittal plane). In cases of DFO, the correction accuracy obtained with PSCG was 1.5 ± 1.4° for femoral anteversion (axial plane), 0.9 ± 0.9° for LDFA (coronal plane) and 0.9 ± 0.9° for PDFA (sagittal plane). The IKSG was improved from 58.0 ± 13.2° to 71.4 ± 10.9 (p = 0.04) and the IKSF from 50.2 ± 14.3 to 87.0 ± 6.9 (p < 0.001). CONCLUSIONS: Using the PSCG for derotational osteotomy allows excellent correction accuracy in all the three planes for femoral and tibial torsional deformities associated with patellofemoral instability. Level of clinical evidence II, prospective cohort study.

Is Longstanding Congenital Muscular Torticollis Provoking Pelvic Malalignment Syndrome?

It has been reported that congenital muscular torticollis (CMT) may result in secondary scoliosis over long-term follow-ups. However, there are few reports on whether CMT causes pelvic malalignment syndrome (PMS). This study aimed to investigate the relationship between CMT and PMS and to determine the factors associated with the development of PMS in children with longstanding CMT. Medical records of 130 children with CMT who had long-term follow-up were reviewed retrospectively. The chi-squared test and logistic regression analysis were used to determine which initial clinical parameters contributed to the development of PMS. Among 130 children with CMT, 51 (39.2%) developed PMS with or without compensatory scoliosis during long-term follow-up, indicating a high prevalence of PMS in children with a CMT history. Initial clinical symptoms such as a limited range of motion of the neck or the presence of a neck mass could not predict the development of PMS. Even if the clinical symptoms are mild, long-term follow-up of children with CMT is essential to screen for PMS.

Accuracy of three dimensional-planned patient-specific instrumentation in femoral and tibial rotational osteotomy for patellofemoral instability.

PURPOSE: Patellofemoral instability can be caused by tibial or femoral torsional deformity. Established surgical treatment options are rotational osteotomies, but the transfer from pre-operative planning to surgical execution can be challenging. Patient-specific instruments (PSI) are proofed to be helpful tools in realignment surgery. However, accuracy of PSI in femoral and tibial rotational osteotomies remains still unknown. Goal of the present study was to evaluate the accuracy of PSI in femoral and tibial rotational osteotomies in a patient population suffering from patellofemoral instability. METHODS: All patients that underwent femoral or tibial rotational osteotomy using PSI in case of patellofemoral instability from October 2015 until April 2019 in our clinic were included. Twelve knees with twelve supracondylar femoral and seven supratuberositary tibial rotational osteotomies could be included. Accuracy of the correction was assessed using pre- and post-operative CT scans based on conventional measurements and, in 3D, based on 3D bone models of the respective patients. RESULTS: CT measurements revealed an absolute difference between planned and achieved rotation of 4.8° ± 3.1° for femoral and 7.9° ± 3.7° for tibial rotational osteotomies without significant difference (p = 0.069). Regarding 3D assessment, a significant difference could be observed for the residual error between femoral and tibial rotational osteotomies in the 3D angle (p = 0.014) with a higher accuracy for the femoral side. CONCLUSION: The application of PSI for femoral and tibial rotational osteotomy is a safe surgical treatment option. Accuracy for femoral rotational osteotomies is higher compared with tibial rotational osteotomies using PSI.

The effects of biomechanical foot orthoses on the gait patterns of patients with malalignment syndrome as determined by three dimensional gait analysis.

[Purpose] The biomechanical effects of foot orthoses on malalignment syndrome have not been fully clarified. This experimental investigation was conducted to evaluate the effects of orthoses on the gait patterns of patients with malalignment syndrome. [Subjects and Methods] Ten patients with malalignment syndrome were recruited. For each participant, kinematic and kinetic data were collected under three test conditions: walking barefoot, walking with flat insoles in shoes, and walking with a biomechanical foot orthosis (BFO) in shoes. Gait patterns were analyzed using a motion analysis system. [Results] Spatiotemporal data showed the step and stride lengths when wearing shoes with flat insoles or BFO were significantly greater than when barefoot, and that the walking speed when wearing shoes with BFO was significantly faster than when walking barefoot or with shoes with flat insoles. Kinetic data, showed peak pelvic tilt and obliquity angle were significantly greater when wearing BFO in shoes than when barefoot, and that peak hip flexion/extension angle and peak knee flexion/extension and rotation angles were significantly greater when wearing BFO and flat insoles in shoes than when barefoot. [Conclusion] BFOs can correct pelvic asymmetry while walking.

Malalignment Syndrome in Runners.

More than 80% of runners are out of alignment. The standard back examination should include assessment of pelvic alignment. An awareness of pelvic malalignment and the the malalignment syndrome is essential to allow one to provide proper care of a runner. The 3 most common presentations usually respond to a supervised, progressive treatment program. The validity of any research into the biomechanics of running should be questioned if the study has failed to look at whether pelvic malalignment was present and whether the altered, asymmetrical biomechanical changes attributable to the malalignment itself could have affected the results of the study.

Biomechanic Analysis of Lower Extremities in Children and Teenagers with Pes Planus

OBJECTIVE: To analyze the biomechanics of young patients with flat foot or malalignment syndrome of lower extremities and to provide some information and strategies in examining and treating them for other researchers or successive studies. METHOD: Between January 2004 and March 2006, 274 patients were engaged who had been diagnosed as flatfoot in 586 patients aged between 0 and 18. All patients were examined physically by one physiatrist to find other biomechanic abnormalities of lower extremities and to measure resting calcaneal stance position (RCSP) angle, bimalleolar angle (BMA). To detect the existence of scoliosis and the difference in leg length, radiographs were taken of the spine and the lower extremities. Flat foot was defined as when either of the feet had lower than -4degrees degrees of RCSP angle. RESULTS: When comparing the value of RCSP angle between right side and left side, the left side was more pronated than the right side. The value of RCSP angle increased in proportion to age but there are other factors that caused the persistence of foot pronation and ligament laxity. The value of BMA tends to increase in proportion to age. The foot was more pronated, the tibia of the same side was more rotated internally and tibia of the other side was more rotated externally. The most common combined biomechanic abnormality of lower extremities was toe-in gait. CONCLUSION: Because the biomechanic effect of a foot could influence the leg, pelvis of the same side and the other side lower extremity, the flat foot should be regarded as an element of malalignment syndrome, anatomical abnormality, and also functional impairment.