The surgical treatment of severe Scheuermann's kyphosis

How to determine the optimal proximal fusion level for Scheuermann kyphosis

OBJECTIVE

To determine optimal proximal fusion levels for instrumented spinal fusion for Scheuermann kyphosis.

METHODS

We reviewed 86 patients (33 women) who underwent corrective instrumented spinal fusion for Scheuermann kyphosis. All patients had long-cassette upright lateral radiographs taken preoperatively, postoperatively, and at 2 years and the last follow-up. Demographic, radiographic, and surgical parameters were compared between patients with and without PJK.

RESULTS

PJK occurred in 28 patients (32%). The mean maximum Cobb angle was 85.8° ± 11.7° preoperatively, 54.8° ± 14.2° postoperatively, and 59.7° ± 16.8° at the last follow-up. Age and sex did not differ between the PJK and non-PJK groups (P > 0.05). The preoperative curve characteristics, fusion levels, and corrective ratio were similar in both groups (P > 0.05). The maximal Cobb angle at 2 years and the last follow-up significantly differed between the 2 groups (P < 0.05). The proportion of patients with the uppermost instrumented vertebra (UIV) at or above the proximal end vertebra (PEV) was similar in both groups (P > 0.05). The proportion of patients with UIV at or above T2 was significantly greater in the non-PJK group (P < 0.05). PJK was significantly associated with a C7 plumb line (C7PL)-sacrum distance ≥ 50 mm (P < 0.05).

CONCLUSION

PJK is the main cause of postoperative correction loss. Proper fusion-level selection can reduce PJK occurrence. We recommend having the UIV at T2 or above, especially when the C7PL-sacrum distance ≥ 50 mm.

[Surgical treatment of kyphosis in children and adolescents]

OBJECTIVE

Correction of a pathological kyphosis to restore a balanced, low-pain or pain-free and load-bearing spine.

INDICATIONS

Pronounced sagittal imbalance, progressive kyphosis despite conservative therapy, and neurological deficits are indications for surgery. Further surgical indications are severe therapy-resistant complaints and/or psychologically burdening cosmetic impairment. The guidelines for surgical indications are kyphosis angles of 75-80° thoracic and 30-50° lumbar.

CONTRAINDICATIONS

No specific, but general contraindications for surgical treatment.

SURGICAL TECHNIQUE

Depending on the characteristics of the kyphosis, different surgical techniques are used. Rod-screw systems are mainly used, and surgery is primarily performed by shortening the spinal column from posterior using a wide variety of techniques. In individual cases, this can be combined with ventrally mobilizing, resecting, or straightening techniques.

POSTOPERATIVE MANAGEMENT

The aim of surgical treatment is to achieve a primarily stable and weight-bearing spine. Regular wound control as well as stabilizing physiotherapy during follow-up are essential. Postoperatively, initially abstaining from sports; later physical activity is encouraged under professional guidance.

RESULTS

The literature shows very good corrective results in children and adolescents. The technical procedures are associated with a low and acceptable complication rate. Over the course of time, these patients must be monitored in order to detect possible long-term complications such as junctional kyphosis or pseudarthrosis.

Scheuermann Kyphosis: Current Concepts and Management

PURPOSE OF REVIEW

Scheuermann's kyphosis (SK) is a developmental deformity of the spine that affects up to 8% of children in the US. Although, the natural progression of SK is noted to be gradual over years, severe deformity can be associated with significant morbidity. Thorough clinical examination and interpretation of relevant imaging help differentiate and confirm this diagnosis. Treatment includes both operative and nonoperative approaches. The purpose of this article is to provide an updated overview of the current theories of its pathogenesis, as well as the principles of diagnosis and treatment of SK.

RECENT FINDINGS

Although a definitive, unified theory continues to be elusive, numerous reports in the past decade provide insight into the pathophysiology of SK. These include alterations in mechanical stress and/or hormonal disturbances. Candidate genes have also been identified to be linked to the inheritance of SK. Updates to nonoperative treatment include the effectiveness of dedicated exercise programs, as well as the types and duration of orthotic treatment. Advances in surgical technique can be observed with a trend toward a posterior-only approach, with supporting evidence for careful evaluation of both the sagittal and coronal planes to determine fusion levels in order to avoid postoperative junctional pathologies. SK is an important cause of structural or rigid kyphosis. It can lead to significant morbidity in severe cases. Treatment is based on curve magnitude and symptoms. Nonoperative treatment consists of physical therapy in symptomatic patients, and bracing can be added for skeletally mature patients. Operative management can be considered in patients with large, progressive, and symptomatic deformity. Future studies can benefit from a focused investigation into patient-reported outcomes after undergoing appropriate treatment.

Selecting the Vertebra above Sagittal Stable Vertebra as the Distal Fusion Level in Scheuermann's Kyphosis: A Prospective Study with a Minimum of 2-Year Follow-Up

OBJECTIVE

The proper selection of the lower instrumented vertebra (LIV) remains controversial in the surgical treatment of Scheuermann's disease and there is a paucity of studies investigating the clinical outcomes of fusion surgery when selecting the vertebra one level proximal to the sagittal stable vertebra (SSV-1) as LIV. The purpose of this study is to investigate whether SSV-1 could be a valid LIV for Scheuermann kyphosis (SK) patients with different curve patterns.

METHODS

This was a prospective study on consecutive SK patients treated with posterior surgery between January 2018 and September 2020, in which the distal fusion level ended at SSV-1. The LIV was selected at SSV-1 only in patients with Risser >2 and with LIV translation less than 40 mm. All of the patients had a minimum of 2-year follow-up. Patients were further grouped based on the sagittal curve pattern as thoracic kyphosis (TK, n = 23) and thoracolumbar kyphosis (TLK, n = 13). Radiographic parameters including global kyphosis (GK), lumbar lordosis (LL), sagittal vertical axis (SVA), LIV translation, pelvic incidence (PI), pelvic tilt (PT), and sacral slope (SS) were measured preoperatively, postoperatively, and at the latest follow-up. The intraoperative and postoperative complications were recorded. The Scoliosis Research Society (SRS)-22 scores were performed to evaluate clinical outcomes.

RESULTS

A total of 36 patients were recruited in this study, with 23 in the TK group and 13 in the TLK group. In TK group, the GK was significantly decreased from 80.8° ± 10.1° to 45.4° ± 7.7° after surgery, and was maintained at 45.3° ± 8.6° at the final follow-up. While in the TLK group, GK was significantly decreased from 70.7° ± 9.2° to 39.1° ± 5.4° after surgery (p < 0.001) and to 39.3° ± 4.5° at the final follow-up. Meanwhile, despite presenting with different sagittal alignment, significant improvement was observed in LL, SVA, and LIV translation for both TK and TLK groups (p < 0.05). Self-reported scores of pain and self-image in TK group and scores of self-image and function in TLK group showed significant improvement at the final follow-up (all p < 0.05). Distal junctional kyphosis (DJK) was observed in two patients (8.7%) in TK group, and one patient (7.7%) in TLK group. No revision surgery was performed.

CONCLUSION

Selecting SSV-1 as LIV can achieve satisfactory radiographic and clinical outcomes for SK patients with different curve patterns without increasing the risk of DJK. This selection strategy could be a favorable option for SK patients with Risser sign >2 and LIV translation less than 40 mm.

Atypical Scheuermann's disease with severe kyphosis and negative sagittal balance in the thoracolumbar region: A case report and literature review

INTRODUCTION AND IMPORTANCE

Scheuermann's kyphosis is a structural deformity of the thoracolumbar spine that is classified in typical (thoracic) and atypical (lumbar and thoracolumbar) Scheuermann's disease. Surgical intervention is reserved for those with progressive kyphosis, intractable pain and neurological impairment. Although, previous literature focuses on the correction of the thoracic kyphosis (TK), recent lines of evidence recommend considering all the sagittal balance parameters when performing a surgery. We herein, report a posterior-only approach in a patient with Scheuermann's kyphosis, considering all the sagittal balance parameters.

CASE PRESENTATION

The patient was a 17-year-old boy with a kyphotic deformity in the lumbar region, with urinary retention and upper back intractable pain. The preoperative physical examination was normal except for a kyphotic gait. The patient was first treated with thoracic lumbosacral orthoses (TLSO) brace that was not effective; consequently, the patient underwent posterior only approach (pedicular screw fixation along with Smith-Peterson osteotomy) with correction of the sagittal balance and kyphosis. The patient's sign and symptoms improved significantly. The surgery was uneventful and no complication was recorded. The 1-year follow-up revealed normal neurological examination and normal sagittal balance parameters.

CLINICAL DISCUSSION

Atypical Scheuermann's kyphosis with neurological impairment and progressive kyphosis should be treated with surgical intervention.

CONCLUSION

Considering the sagittal parameters of the spine, the surgical intervention should be designed to correct the kyphosis and the other indices of the sagittal balance. Posterior-only approach is safe and effective method for correction of the TK and improving the signs and symptoms of the patients.

Health-related quality of life outcomes in adolescent Scheuermann's kyphosis patients treated with posterior spinal fusion: A comparison with age- and sex-matched controls

PURPOSE

To assess the health-related quality of life and radiographic outcomes of surgically treated adolescent Scheuermann's kyphosis patients after minimum of 2-year follow-up and to compare the health-related quality of life with age- and sex-matched healthy controls.

METHODS

Twenty-two consecutive adolescents (mean age = 16.7 years) undergoing posterior spinal fusion for Scheuermann's kyphosis were included and matched by age and sex with two healthy controls. The health-related quality of life was evaluated using the Scoliosis Research Society-24 questionnaire. Radiographic parameters were measured for comparison preoperatively and at 6 months and 2-year follow-ups. The health-related quality of life parameters were compared with healthy controls at 2 years of follow-up.

RESULTS

The mean maximal thoracic kyphosis improved from 79° (range = 75°-90°) to 55° (range = 45°-75°) (p < 0.001), and the mean lumbar lordosis was reduced from 71° (range = 51°-107°) to 52° (range = 34°-68°) (p < 0.001) after 2 years postoperatively. Incidence of proximal junctional kyphosis (PJK) was 18%. The scores of the Scoliosis Research Society-24 improved, with statistical significance observed in pain and self-image domains from preoperative to 2-year follow-up (p = 0.002 in both domains). The self-image and function were significantly lower in the operated patients at their 2-year follow-up visit compared to controls (p = 0.023 for self-image and p < 0.001 for function).

CONCLUSION

Instrumented posterior spinal fusion improves the health-related quality of life of Scheuermann's kyphosis patients during the 2-year follow-up. The greatest improvement is observed in pain and self-image domains. The health-related quality of life in pain and activity domains reaches the level of healthy individuals, while function and self-image remain at a statistically lower level.