Medium Term Outcomes in Palliative Transpedicular Corpectomy with Cement Based Anterior Vertebral Reconstruction Performed for Patients with Spinal Metastasis.

STUDY DESIGN: Retrospective. OBJECTIVE: Assess the outcomes of single stage posterior transpedicular corpectomy with cement-based anterior column support for spinal metastasis at longer follow-ups. SUMMARY OF BACKGROUND DATA: Life expectancy of cancer patients is constantly increasing. Reliable anterior column reconstruction after posterior corpectomy becomes necessary. METHODS: In this retrospective monocentric study, patients who underwent posterior transpedicular corpectomy and cement-based anterior reconstruction, with a minimum 6 months follow-up, were included. Ambulatory status and pain visual analog score(PVAS), complication rates and Local Sagittal Cobb angle (LSA) were evaluated preoperatively, postoperatively and at the latest follow-up. RESULTS: In total, 253 patients were included, with a mean follow-up of 21 months [6-132] and a median survival of 9 months. Pre-operatively, 202 patients(81%) were ambulant while 47 patients (19%) weren't. At the latest follow-up, 241 patients (95%) were ambulant while 12 patients(5%) weren't (P<0.001). Dorsal/lumbar PVAS went from 8.2±2.2 pre-operatively to 5.2(±1.7) post-operatively reaching 3.4±1.9 at the latest follow-up (P<0.001). Mean LSA decreased from 13.2°(±5.78) pre-operatively to 6.11°(±8.51)(P<0.001) post-operatively and reached 7.56°(±7.55) at the latest follow-up(P=0.59). Complications occurred in 39(15.4%) patients. One-third of those were mechanical(rod/screw fracture, cement displacement) needing re-intervention in 4 patients(1.6%). CONCLUSIONS: The mechanical stability offered by the cement-based anterior reconstruction is maintained during the lifespan of patients operated for the spinal metastasis. Satisfying functional and radiological outcomes observed at the last follow-up show that this lasting, cost sparing, and relatively simple reconstruction technique, is a valid alternative for the costly and more complicated cage-based reconstruction.

Bone Allograft Pedicle Screw Augmentation: A Biomechanical Study.

STUDY DESIGN: We performed a comprehensive cadaveric biomechanical study to compare the fixation strength of primary screws, screws augmented with bone allograft, and screws augmented with polymethylmethacrylate cement. OBJECTIVE: To evaluate a novel technique for screw augmentation using morselized cortico-cancellous bone allograft to fill the widened screw track of failed pedicle screws. BACKGROUND: To date, there are no known biological methods available for failed pedicle screw augmentation or fixation. MATERIALS AND METHODS: Biomechanical tests were performed using 2 different testing modalities to quantify fixation strength including axial screw pullout and progressive cyclic displacement tests. RESULTS: Fifty vertebrae were instrumented with pedicle screws. Our study showed that bone allograft augmentation using the same diameter screw was noninferior to the fixation strength of the initial screw. In the axial pullout test, screws undergoing bone allograft repair failed at 25% lower loads compared with native screws, and screws augmented with cement showed approximately twice as much strength compared with native screws. In the cyclic displacement test, screws fixed with cement resisted loosening the best of all the groups tested. However, screws augmented with bone graft were found to have an equal strength to native screw purchase. our study did not find a correlation with bone mineral density as a predictor for failure in axial pullout or cyclic displacement tests. CONCLUSION: Bone allograft augmentation for pedicle screw fixation was noninferior to the initial screw purchase in this biomechanical study. This bone allograft technique is a viable option for screw fixation in the revision setting when there is significant bone loss in the screw track.

Can Pelvic Incidence Change After Lumbo-Pelvic Fixation for Adult Spine Deformity, and Would the Change be Affected by the Type of Pelvic Fixation?

STUDY DESIGN: Retrospective review. OBJECTIVE: To assess the change in pelvic incidence (PI) after lumbo-pelvic fixation and the differential impact of the type of pelvic fixation: S2-alar-iliac screws (S2AI) versus Iliac screws (IS) on postoperative PI. SUMMARY OF BACKGROUND DATA: Recent studies suggest that changes occur to the previously assumed fixed PI after spino-pelvic fixation. METHODS: Adult spine deformity (ASD) patients who underwent spino-pelvic fixation with≥4 levels of fusion were included. Preoperative and postoperative PI, lumbar lordosis (LL), thoracic kyphosis, pelvic tilt, sacral slope, PI-LL mismatch, and the Sagittal Vertical Axis (SVA) were analyzed on EOS imaging. A significant PI change was established at≥6°. Patients were categorized based on the type of pelvic fixation (S2AI vs. IS). RESULTS: One-hundred-forty-nine patients were included. Of these, 77(52%) had a>6° change in their PI postoperatively. In patients with high preoperative PI (>60°), 62% had a significant PI change compared with 33% of patients with normal PI (40°-60°) and 53% in patients with low PI (<40°; P =0.01). PI was likely to decrease in patients with high baseline PI (>60°) and to increase in patients with low baseline PI (<40°). Patients with a significant PI change had a higher PI-LL. Patients in the S2AI group (n=99) and those in the IS group (n=50) were comparable at baseline. In the S2AI group, 50 (51%) patients had>6° change in their PI compared with 27(54%) patients in the IS group( P =0.65). In both groups, patients with high preoperative PI were more prone to significant postoperative changes ( P =0.02 in IS, P =0.01 in S2AI). CONCLUSION: PI changed significantly in 50% of patients postoperatively, especially in those with high/low preoperative PI and those with severe baseline sagittal imbalance. This occurs similarly in patients with S2AI and those with IS screws. Surgeons should keep in mind these anticipated changes while planning ideal LL, as this impacts postoperative PI-LL mismatch. LEVEL OF EVIDENCE: 4.

How Does Spino-Pelvic Fixation Affect Post-Operative Compensatory Mechanisms in Adult Spinal Deformity?

STUDY DESIGN: Retrospective single-center multi-surgeon cohort study. OBJECTIVES: Compare the post-operative changes in the compensatory mechanisms of the sagittal balance according to the type of pelvic fixation: S2-Alar-iliac screws (S2AI) vs iliac screws (IS) in patients with Adult spine deformity (ASD). METHODS: ASD patients who underwent spino-pelvic fixation and remained with a PI-LL >10° mismatch post-operatively were included. Pre-operative and 1-year-follow-up PI, Lumbar lordosis (LL), pelvic tilt (PT), sacral slope (SS), thoracic kyphosis (TK), femur obliquity angle (FOA), knee flexion angle (KFA) and ankle flexion angle (AFA) were analyzed on EOS imaging. Patients were categorized based on their pelvic fixation type (S2AI vs IS), and the pre-operative to 1-year-post-operative changes (ΔX°) in the compensatory mechanisms were compared between groups. RESULTS: Patients with S2AI (n = 53) and those with IS (n = 26) screws were comparable at baseline. ΔSS averaged 9.87° in the S2AI compared to 13.2° in the IS (P = .001), whereas the ΔKFA reached 6.01° in the S2AI as opposed to 3.06° in the IS (P = .02). The ΔPT was comparable between both groups (6.35°[S2AI group] vs 5.21°[ISgroup], P = .42). ΔTK, ΔLL, ΔFOA and ΔAFA were comparable between both groups. CONCLUSION: The type of pelvic fixation impacts significantly the post-operative compensatory mechanisms in patients with ASD. Patients with S2AI screws are more likely to compensate their remaining post-operative PI-LL mismatch through their knees and less likely through their pelvis compared to patients with IS, despite similar changes in PT. This could be explained by an increased SI joint laxity in ASD patient and the lower resistance of the iliac connectors to the junctional mechanical stresses, allowing for sacro-iliac joint motion in patients with IS.

The Saint-Joseph Acetabular score: a reproducible and accurate prediction of the outcome of open reduction and internal fixation of acetabular fractures.

PURPOSE: Acetabular fractures are associated to an increased risk of subsequent hip osteoarthritis. The only available score for post-operative reduction assessment in acetabular fractures (Matta's score) is x-ray based. CT-scan was shown superior to X-rays in post-operative reduction assessment. We aim to describe a CT-scan-based post-operative reduction score in acetabular fractures and evaluate its accuracy and reproducibility. METHODS: This is a retrospective study that includes 138 patients who underwent surgery for an acetabular fracture in our tertiary referral centre with a mean follow-up of 104.39±42.2 months. The post-operative CT-scan was reviewed and residual displacement (maximum gap and step) measured by three independent observers. The association between the occurrence of THA and the CT-scan measurements was evaluated. This led to a new prognostic score. The interobserver reliability and accuracy of this score were calculated. RESULTS: Interobserver reproducibility for the residual maximal gap was 0.82 (95% CI [0.70-0.89]) and 0.61 (95% CI [0.52-0.70]) for the residual maximal step displacement measurements. We created a score from a logistic regression model, attributing 1 point for every 1 mm of residual maximal step displacement and 1 point for every 2 mm of residual maximal gap displacement. The interobserver reproducibility of this score was 0.78 (95% CI [0.71-0.84]), and its AUC was 0.79 (95% CI [0.69-0.88]). CONCLUSION: This is the first CT-scan-based score for the assessment of residual displacement of a surgically treated acetabular fracture. It shows good interobserver reproducibility and accuracy in predicting the risk for secondary THA. It should be regularly used per-operatively (if per-operative 3D imaging is available) and post-operatively to predict the prognosis.

Primary Sarcomas of the Spine: A Systematic Review and Pooled Data Analysis.

STUDY DESIGN: A systematic review of the literature and pooled data analysis of treatment outcomes of primary sarcomas of the spine. OBJECTIVE: To examine the current literature and treatment options for primary sarcomas of the spine. SUMMARY OF BACKGROUND DATA: A paucity of literature exists on treatment outcomes of primary sarcomas of the spine. MATERIALS AND METHODS: Two authors searched PubMed to identify articles for review, and a pooled data analysis was performed to determine overall survival for each type of surgical resection on spine sarcomas. RESULTS: In total, 1776 articles were identified, and 11 met our inclusion criteria for review. In chondrosarcoma, overall survival was significantly higher with en bloc excision when compared with piecemeal resection (HR for piecemeal resection: 4.11; 95% CI: 2.08-8.15). Subgroup analysis showed that the addition of radiation therapy after piecemeal excision increased overall survival to 60 months from 48 months with piecemeal excision alone. In osteosarcoma, there was no significant difference in overall survival between en bloc and piecemeal resection (HR for piecemeal resection: 1.76; 95% CI: 0.776-3.99). In Ewing's sarcoma, overall survival was significantly higher when a successful en bloc resection was achieved and coupled with chemotherapy and radiation therapy for local control (HR for piecemeal resection: 7.96; 95% CI: 2.12-20.1). Interestingly, when a successful en bloc resection could not be achieved, chemotherapy and radiation therapy alone had significantly higher survival than piecemeal resection (HR for piecemeal resection: 2.63; 95% CI: 1.01-6.84). A significantly higher number of local recurrences were associated with the piecemeal resection group in all types of spine sarcomas. CONCLUSION: This review and pooled data seem to favor en bloc excision for local control as the treatment of choice in primary sarcomas of the spine.

LUMiC® endoprosthesis for pelvic reconstruction: A Canadian experience.

BACKGROUND AND OBJECTIVES: The LUMiC® prosthesis was introduced to reduce the mechanical complications encountered with periacetabular reconstruction after pelvic tumor resection. Few have evaluated the outcomes associated with its use. METHODS: A retrospective study from five Orthopedic Oncology Canadian centers was conducted. All patients with a LUMiC® endoprosthesis were included. Their charts were reviewed for surgical and functional outcomes. RESULTS: A total of 16 patients were followed for 28 months (3-60). A total of 12 patients (75%) had a LUMiC® after a resection of a primary sarcoma. Mean surgical time was 555 min. Four patients (25%) had a two-stages procedure. MSTS score was 60.3 preoperatively and 54.3 postoperatively. Patients got a dual mobility bearing and the silver coated implant was used in 7 patients (43.7%). Five patients (31.3%) underwent capsular reconstruction using a fabric. Silver-coating was not found to reduce infection risk (p = 0.61) and capsuloplasty did not prevent dislocation (p = 0.6). Five patients had peroperative complications (31.3%). Eight patients (50%) had an infection including all four with two-stages surgery. Dislocation occurred in five patients (31.3%) whereas no cases of aseptic loosening were reported. A total of 10 patients (62.5%) needed a reoperation. CONCLUSION: LUMiC® endoprosthesis provides low rates of aseptic loosening on medium-term follow-up. Infection and dislocation are common complications but we were unable to show benefits of capsuloplasty and silver-coated implants.

Outcomes After Abductor Reattachment to Proximal Femur Endoprosthesis After Tumor Resection.

INTRODUCTION: Resection of the proximal femur raises several challenges including restoration of the abductor mechanism. Few evaluated the outcomes of different techniques of abductor fixation to the proximal femur endoprosthesis. METHODS: A retrospective review of patients who underwent proximal femoral arthroplasty with a minimum follow-up of 12 months was conducted. Patients were divided into two groups: (1) those with preserved greater trochanter (GT) reattached to the implant and (2) those with direct abductor muscle reattachment. Both groups were compared for surgical and functional outcomes. Group 1 patients were subdivided into those who received GT reinsertion using grip and cables and those reattached using sutures. RESULTS: Fifty-three patients were included with a mean follow-up of 49 months. There were 22 patients with reinserted GT and 31 patients with soft-tissue repair. The endoprosthesis revision rate was comparable between groups (P = 0.27); however, the incidence of dislocations was higher in group 2 (0/22 versus 6/31; P = 0.035). Trendelenburg gait (77% versus 74%), use of walking aids (68% versus 81%), and abductor muscle strength were comparable between both groups (P > 0.05). In group 1, 15 patients had GT reinsertion with grip and cables. Of those, five patients (33%) had cable rupture within 13 months of follow-up. GT displacement reached 12 mm at 12 months of follow-up in patients with grip and cables compared with 26 mm in patients with GT suture reinsertion (P < 0.05). DISCUSSION: Although GT preservation did not improve functional outcomes, it was associated with a lower dislocation rate despite frequent cable failure. Less displacement was observed when GT reattachment used grip and cables.

Joint-sparing reconstruction for extensive periacetabular metastases: Literature review and a novel minimally invasive surgical technique.

Classically, patients with advanced lytic disease of the acetabulum secondary to metastatic bone disease are treated with complex arthroplasty reconstruction techniques. Advancements in percutaneous techniques have extended the indications for safer, minimally invasive procedures for patients with periacetabular metastasis without the need for complex hip replacement and the complications that follow it. The purpose of this report is to revisit the management of this group of patients and provide indications for an alternative minimally invasive joint-sparing technique. We describe a novel technique using a combination of percutaneous cryoablation, cementoplasty and two-screw fixation. With careful consideration of indications, excellent functional and oncologic outcomes one year after surgery is possible without the need for additional procedures.

Clubfoot management in the Middle East: a survey-based review.

Clubfoot is the most frequent congenital deformity involving the foot. Little is known about the management of this disease in the Middle East as sparse data is available in the literature. Through the last 5 decades, congenital clubfoot management in the Middle East went from manipulation through Kite's technique in the late seventies, to early primary surgical intervention in the late eighties and early nineties of the previous century, and then back to manipulation with Ponseti's technique and the French functional technique in the late nineties, with the latter falling out of favor with time. This is comparable to the evolution of management witnessed in the United States and in Europe, with 10 to 15 years of delay. The delay is getting shorter with time due to the easier access to published scientific data and the increasing number of fellows from Middle East travelling to referral centers in Europe and the USA. A survey was performed among pediatric orthopedic surgeons in the Middle East to assess their approach to clubfoot management. This is the first survey of its kind in the region. It showed a wide adoption (97.1%) of the Ponseti's technique with serial manipulation and casting, Achilles tenotomy followed by abduction bracing. Divergent practices were found concerning the upper age limit for Ponseti treatment and the setting of the Achilles tenotomy. Nevertheless, these subjects are still a matter of debate in the literature and international conferences. All in all, pediatric orthopedic surgeons in the Middle East are offering their patients the gold standard of care. However, lot of work is to be done in raising awareness for this disease in the community, and among our colleagues as prenatal screening for clubfoot in the Middle East is practically nonexistent.

Clinical impact of intraoperative cone beam tomography and navigation for displaced acetabular fractures: a comparative study at medium-term follow-up.

INTRODUCTION: The use of per-operative cone beam tomography imaging for displaced acetabular fractures yields increased post-operative articular reduction accuracy. This study evaluates the need for total hip replacement (THR) and hip-related functional outcomes in patients with displaced acetabular fractures treated with O-ARM guidance compared to those treated under C-ARM guidance. MATERIALS AND METHODS: This is a prospective matched cohort study. Adult patients (35) with acetabular fractures operated under O-ARM guidance were included. These were matched (age, fracture type) to classically treated patients (35) from our data base. The primary outcome was the need for THR during three year follow-up period. Secondary outcomes were functional scores [Harris Hip score (HHS), Postel-Merle d'Aubigné (PMA)] and hip osteoarthritis grade at three year follow-up. Correlation between reduction gap and THR was evaluated. RESULTS: At three years, five patients were lost to follow-up in O-ARM group and four in control group. Two patients (6.66%) in the O-ARM group needed THR compared to eight patients in controls (25.80%) (p = 0.046). Hip X-ray osteoarthritis grade averaged 0.00 in patients without THR in O-ARM group compared to 0.22 in patients without THR in controls (p = 0.008). HHS averaged 95.79 in patients without THR in O-ARM group, compared to 93.82 in patients without THR in the control group (p = 0.41%). PMA averaged 17.25 in patients without THR in the O-ARM group compared to 17.04 in patients without THR in group 2 (p = 0.37). Evaluation of correlation between reduction gap and THR rate yielded OR = 1.22 (1.06-1.45). DISCUSSION: Increased accuracy in articular reduction, with per-operative three-dimensional control of impaction, in acetabular fractures led to significantly less need for THR in patients treated under O-ARM. Patients in both groups are comparable for functional outcomes because those with the lowest scores were offered THR. Per-operative cone beam guidance and navigation use are recommended in tertiary referral centres for acetabular trauma.

Modified Stoppa Approach: Beyond Acetabular Fractures: A Report of 2 Cases.

CASES: We used the modified Stoppa approach in a 17-year-old man with a retained bullet in his acetabular fossa. The acetabular hole was used to irrigate the hip joint. We also used this approach in a 29-year-old woman with right hip pain and limping to remove an isolated tenosynovial giant cell tumor ("localized pigmented villonodular synovitis") in the acetabular fossa expanding through the acetabulum. DISCUSSION: We believe that this approach should become more familiar because it offers a simple alternative for treating acetabular pathologies mainly involving the acetabular fossa, sparing patients the hazards of capsulotomy, trochanteric osteotomy, dislocation, and traction and fluid pressure in hip arthroscopy.

Revisiting thoracic kyphosis: a normative description of the thoracic sagittal curve in an asymptomatic population.

PURPOSE: Thoracic kyphosis (TK) remained in the shadow of lumbar lordosis. Based on Berthonnaud and Roussouly segmentation, TK is divided into two arches: upper TK (UTK) and lower TK (LTK). The purpose of this study is to propose a normative description of the TK arches in an asymptomatic adults' population and their correlation with spinal and pelvic parameters. METHODS: This is an observational study performed on asymptomatic healthy Caucasians volunteers aged between 18 and 45 years. Each patient had a standardized standing biplanar full spine X-rays. Using KEOPS®, sacropelvic parameters and global spinal parameters (LL, TK) as well as the inflexion point location were measured. The upper lumbar lordosis angle (ULL) as well as LTK and UTK was calculated. Patients were classified according to Roussouly morphotypes of normal spine. RESULTS: A total of 373 adults (F/M = 1.4/1) were enrolled with mean age of 27 years. Mean UTK averaged 25.8°, while mean LTK averaged 19.8° (p < 0.001). UTK angle values were statistically the same in the five different Roussouly spinal shapes (p > 0.05), while LTK values were variable among different Roussouly spine subtypes (p < 0.05). Finally, TK showed the highest correlation with the LL mainly with the ULL (Pearson = 0.66). CONCLUSION: In asymptomatic young adults, thoracic kyphosis is composed by two unequal arches, a stable UTK and a variable LTK, with an apex around T8 and T9 vertebra, depending on the spinal morphotype according to Roussouly classification. This should be taken into consideration when analyzing spine sagittal compensation and preparing corrections to minimize risk of mechanical complications.

Knee injuries concomitant to posterior acetabular fractures: an association to look for.

PURPOSE: Acetabular fractures are frequently associated with other skeletal injuries, particularly knee injuries. This study aims to evaluate the relationship between posterior acetabular fractures and knee injury, analyzing its patterns and association with other injuries. METHODS: This is a retrospective monocentric study in a tertiary referral centre. We reviewed the data (age, sex, type of fracture, and concomitant injury) of patients hospitalized for a posterior acetabular fracture. We recorded concomitant knee injury diagnosed up to one year following acetabular fracture. RESULTS: Two-hundred-seventeen patients (177 males/40 females) were included. The mean age was 40.5 years. Eighty-five patients (39%) had a concomitant hip dislocation, nine (4.1%) had sciatic nerve palsy, 17 (7.8%) had upper extremity injury, and 18 (8.3%) had lower extremity injury (other than the knee). Eight (3.7%) patients had spine injury, 11 (5.1%) had severe thoracic injury, nine (4.1%) had an abdominal injury, and four (1.8%) had a head injury. There were 33 (15.21%, 95% CI 10.80-20.8%) patients (30 M/3 F) (group 1) with a concomitant knee injury and 184 patients without a concomitant knee injury(group 2). The mean age in group 1 was 34.3 compared to 45.4 in group 2(p = 0.021). The pattern analysis revealed five fractures, 14 ligamentous injuries (PCL injuries = 68%), and 14 soft tissue injuries. Sixteen (48.48%) injuries were identified during hospitalization and 17 (51.51%) during follow-up. There were an association between knee injury and upper extremity injury (OR = 3.49 95% CI 1.12-10.00,p = 0.022) and other lower extremity injury (OR = 3.18 95% CI 1.03-8.95,p = 0.032). DISCUSSION: Knee injury is the second most frequent lesion associated with posterior acetabular fractures. Being missed in half of cases, we recommend a systematic examination of ipsilateral knees under general anaesthesia, keeping a high index of suspicion and a low threshold for complementary knee imaging. Knee injury should be mainly looked for in patients younger than 60 years and in those with upper and/or lower extremities injuries.

Comparison of morbidity and mortality of hip and vertebral fragility fractures: Which one has the highest burden?

OBJECTIVES: Hip fragility fractures were regarded as one of the most severe, but recent papers report on the underestimated burden of vertebral compression fractures. This study aims to compare morbidity and mortality of hip and vertebral fragility fractures in patients treated in the same setting. METHODS: Patients aged ≥50 years with hip fracture, and those with vertebral fracture presenting to our hospital between January 2014 and January 2017 were included. Patients were evaluated 1 year after their index fracture. SF-36 scores, mortality, and institutionalization are then recorded. Patients were divided into 2 groups: hip fractures and vertebral fractures. RESULTS: There were 106 and 90 patients respectively evaluated in hip and vertebral fracture groups at 1 year. Patients in both groups were comparable for age, sex, comorbidities and neuropsychiatric condition (P > 0.05). At 1 year follow-up, SF-36 showed better averages in all 8 scales in hip fracture group compared to vertebral fracture group. Mortality in the hip fracture group reached 32.1% compared to 10% for the vertebral fracture group (P < 0.01). Fifteen patients were institutionalized in the hip fracture group compared to 18 patients in the vertebral fracture group (P > 0.05). CONCLUSIONS: When comparing patients treated in the same setting, hip fracture is associated with significantly increased mortality than vertebral fracture; however, the latter is associated with more morbidity.

Is There Still a Place for Convex Hemiepiphysiodesis in Congenital Scoliosis in Young Children? A Long-Term Follow-up.

STUDY DESIGN: Retrospective cohort. OBJECTIVES: To evaluate the long-term effect of convex growth arrest (CGA) on coronal deformity correction in congenital scoliosis. METHODS: Twenty-two patients with congenital scoliosis operated by 1-staged double approach hemiephysiodesis by bone grafting of the convex side without instrumentation are included. Eighteen curves had an isolated hemivertebra while 4 curves had congenital bar. Subgroup analysis was performed according to age at surgery (3 years cutoff), type of malformation (hemivertebra vs congenital bar), and severity of curve (35° cutoff). RESULTS: Patients' mean age at surgery was 3 years (range 0.5-8 years), with a mean frontal Cobb angle of 40.59°. Mean follow-up is 10.7 years (range 5.5-25 years). Overall results showed mean frontal Cobb angle reduction of 35.47% (40.59° to 27.41°). Detailed analysis showed that 15 curves had a mean correction of 51.8%, 5 stabilized and 2 had a mean aggravation of 25.11%. Subgroup analysis revealed that patients operated ≤3 years of age had mean cobb angle correction of 43.1% versus 21.49% in patients operated >3 years (P = .140). Mean correction of 44.5% was gained in curves with isolated hemivertebra compared with 1.3% in curves with congenital bar (P = .004). A 58.17% mean correction was reached in curves ≤35° versus 23.68% in curves >35° (P = .032). CONCLUSIONS: A limited convex hemiepiphysiodesis still has a place in congenital scoliosis care when it is performed in patients ≤3 years old, with curves ≤35°, and with isolated hemivertebra. It spares patients the risks of vertebral resection and instrumentation, while fusing the same number of levels.

The impact of residual growth on deformity progression.

Idiopathic scoliosis is a disease of the growing spine. Risk of progression and aggravation of disease are mainly dictated by the remaining growth and curve magnitude. Remaining growth can be estimated by repeated biometric measurements, tanner sign and bone age estimation. Puberty is the turning point in the natural history of this disease. The first two years following puberty are the turning point in the natural history of this disease since 90% of growth occurs during this period. Lateral olecranon radiograph is effective for estimating bone age during this phase. Growth acceleration is followed by a deceleration phase of three years where menarche occurs. Bone age during this phase is evaluated by hand X-rays and the Risser sign. Progression risk assessment of idiopathic scoliosis showed that a 30° curve at the beginning of puberty together with 20° to 30° curves with more than 10° of annual curve progression has a 100% risk of progression towards the 45° surgical threshold. In these patients, anticipation may be the key for effective treatment strategy. Treating these curves earlier than the surgical threshold before increased stiffness would lead to a better outcome.