Sustained hip flexion contracture after femoral lengthening in patients with achondroplasia

Interventions for improving clinical outcomes and health-related quality-of-life for people living with skeletal dysplasias: an evidence gap map

PURPOSE

Skeletal dysplasias are rare genetic disorders that are characterized by abnormal development of bone and cartilage. There are multiple medical and non-medical treatments for specific symptoms of skeletal dysplasias e.g. pain, as well as corrective surgical procedures to improve physical functioning. The aim of this paper was to develop an evidence-gap map of treatment options for skeletal dysplasias, and their impact on patient outcomes.

METHODS

We conducted an evidence-gap map to identify the available evidence on the impact of treatment options on people with skeletal dysplasias on clinical outcomes (such as increase in height), and dimensions of health-related quality of life. A structured search strategy was applied to five databases. Two reviewers independently assessed articles for inclusion in two stages: titles and abstracts (stage 1), and full text of studies retained at stage 2.

RESULTS

58 studies fulfilled our inclusion criteria. The included studies covered 12 types of skeletal dysplasia that are non-lethal with severe limb deformities that could result in significant pain and numerous orthopaedic interventions. Most studies reported on the effect of surgical interventions (n = 40, 69%), followed by the effect of treatments on dimensions of health quality-of-life (n = 4, 6.8%) and psychosocial functioning (n = 8, 13.8%).

CONCLUSION

Most studies reported on clinical outcomes from surgery for people living with Achondroplasia. Consequently, there are gaps in the literature on the full range of treatment options (including no active treatment), outcomes and the lived experience of people living with other skeletal dysplasias. More research is warranted to examine the impact of treatments on health-related quality-of-life of people living with skeletal dysplasias, including their relatives to enable them to make preference- and valued based decisions about treatment.

Improvement of the sagittal alignment of the spine in patients with achondroplasia after subtrochanteric femoral lengthening

PURPOSE

Limb-lengthening surgery to treat short stature has undergone great development in recent years with the use of intramedullary telescopic nails (TIMNs). A limited number of studies have explored the impact of lower limb lengthening on the spine, though their conclusions are not consistent. The aim of this research is to analyze changes in spinopelvic sagittal alignment and balance after lower limb lengthening in achondroplastic patients.

METHODS

Prospective study of patients with achondroplasia treated with bilateral femoral lengthening using an TIMN. Different sagittal spinal and pelvic plane parameters were measured on pre- and 2 year postoperative lateral spine radiographs: cervical lordosis, thoracic kyphosis, TL junction, lumbar lordosis (LL), pelvic incidence, pelvic tilt (PT), sacral slope (SS), and sagittal vertebral axis (SVA). Similarly, information regarding the elongation procedure was recorded.

RESULTS

A total of 10 patients were included (60% male), with a median age of 13.39 (2.32) years at first surgery and a median height of 120.3 (5.75) cm. A 10 cm elongation was performed in all patients through femoral subtrochanteric osteotomy. Statistically significant changes were found in LL -15.2 (7.4-17.9)º (p = 0.028), PT 11.7 (10.3-13.4)º (p = 0.018), SS - 11.6 (- 13.4 to - 10.4)º (p = 0.018) and |SVA| - 34.3 (- 39.10 to - 1.7) mm (p = 0.043).

CONCLUSION

Bilateral lower limb lengthening in patients with achondroplasia not only increases their size, but also improves sagittal spinopelvic alignment and balance. This may be due to retroversion of the pelvis and subsequent decrease in SS and LL as a result of the increased tightness of the gluteus maximus and hamstring muscles after femoral lengthening through subtrochanteric osteotomy.

LEVEL OF EVIDENCE

II, prospective comparative cohort study, before and after intervention.

Two-stage Bone Lengthening With Reuse of a Single Intramedullary Telescopic Nail in Patients With Achondroplasia

BACKGROUND

Patients with achondroplasia may benefit from limb-lengthening surgery with telescopic intramedullary nails (TIMNs). However, the 5-cm maximum length of the nails used in these patients in their original design may be insufficient. The aim of this research is to analyze the outcomes and complications after reusing the same TIMN for a second consecutive 5-cm lengthening in patients with achondroplasia.

METHODS

Retrospective study of 26 bones (16 femurs and 10 tibias) in 9 patients with achondroplasia treated for bilateral 2-stage sequential lengthening reusing the same TIMN. On completion of a first stage of 5 cm of elongation, the nail was unlocked, retracted, and re-locked; a second stage of 5 cm of distraction followed. Radiologic and clinical parameters were measured preoperatively and postoperatively, and complications were recorded.

RESULTS

The median age of patients at first surgery was 13.54 (12.9 to 16.3) years; 55% were males. The median preoperative height was 121 (117.5 to 127) cm, and the median healing index was 18.12 (14.5 to 32.8) and 26.96 (23.3 to 31.6) d/cm, while time to weight bearing was 185.5 (144.8 to 308.5) and 242.5 (208.5 to 293.8) days for femurs and tibias, respectively. Major complications included 3 cases of moderate ankle equinus, 2 cases of hardware failure (failure to relengthen), 2 premature consolidations, 1 common peroneal neurapraxia, and 2 valgus deformities. Femoral procedures had significantly fewer complications than tibial interventions (7 vs. 15, P=0.03), whereas patients who underwent lengthening of both the femur and tibia did not have significantly higher complication rates (14 vs. 8, P=0.6).

CONCLUSIONS

This study analyzes lower-limb lengthening in a series of achondroplastic patients using TIMN with the novelty of nail reuse to relengthen the bone. The complication rate found is acceptable, among which, potential damage to the internal lengthening mechanism must be considered, though this complication can usually be easily resolved. Overall, nail reuse seems advisable in cases where bone elongation is indicated, and the size and design of the nail limits the extent of lengthening.

LEVEL OF EVIDENCE

Level III, retrospective comparative study, before and after intervention.

Femoral Lengthening in Children: A Comparison of Motorized Intramedullary Nailing Versus External Fixation Techniques

BACKGROUND

Femoral lengthening is associated with high complication rates often related to the type of surgical device used to perform the lengthening. The advent of intramedullary lengthening devices has promised a reduction in complications when compared with external fixation systems. The purpose of this study was to compare the clinical outcomes of femoral lengthening in children using a motorized intramedullary nail (Precice) versus an external fixation system (Taylor Spatial Frame-TSF; or Monolateral Rail System-MRS) at a single institution, single surgeon practice.

METHODS

This study is a retrospective comparison of pediatric patients who had previously undergone femoral lengthening (±deformity correction). Patients ages 8 to 18 years of age were included and grouped based on whether they had undergone Precice nailing or external fixation (TSF or MRS) between 2010 and 2019.

RESULTS

Twenty-seven patients (32 femurs) were included. Thirteen patients (15 femurs) had undergone Precice nailing and 14 patients (17 femurs) had undergone external fixation. The Precice group had significantly fewer problems, obstacles, and complications than the external fixation group, Precice 6.6%, 0%, 0%, respectively, and external fixation 47.1%, 29.4%, 0% respectively (P<0.01). Unplanned return to the operating room occurred in 4 cases, solely in the external fixation group. There were no differences in percentage of goal length achieved, Precice (mean 93.6%, range: 66.7% to 114.3%), external fixation (mean 96%, range: 76.9% to 117.5%) P=0.31 and total length achieved, Precice (mean: 44 mm, range: 20 to 80 mm), external fixation (mean: 46 mm, range: 10 to 70 mm) P=0.72. There was no difference in consolidation index, Precice (24.1 d/cm), external fixation (28.5 d/cm) P=0.36. The Precice group had a significantly shorter length of stay (mean: 2.2 d, range: 1 to 4 d), compared with the external fixation group (mean: 3.7 d, range: 2 to 8), P=0.01.

CONCLUSIONS

Femoral lengthening in children using a motorized intramedullary nail was associated with a markedly reduced rate of complications and shorter length of stay compared with external fixation.

LEVEL OF EVIDENCE

Level III.

Efficacy and safety of botulinum toxin type A in distraction osteogenesis of the lower extremities: a meta-analysis of randomized controlled trials

Background

To explore the efficacy and safety of botulinum toxin in patients who received distraction osteogenesis of the lower extremities.

Methods

We searched the PubMed, Medline, Cochrane Library, and Web of Science databases for randomized controlled trials that administered botulinum toxin to individuals who underwent distraction osteogenesis of the lower limbs. The final search was conducted on July 6, 2021. Quality assessments were conducted using the Cochrane risk of bias tool and the Jadad scale. We performed random-effects meta-analysis to calculate the standardized mean differences (SMDs) and confidence intervals (CIs) of the pooled effect sizes, and subgroup analysis and meta-regression were performed for potential moderators.

Results

Our analysis of four randomized controlled trials, which enrolled a total of 257 participants, revealed that the difference in pain during the distraction phase was not statistically significant between groups (SMD, − 0.165; 95% CI, − 0.379 to 0.050, p = 0.133, I² = 0.0%). The meta-regression analyses did not find any influence on the effect size, considering age (β = − 0.0092; p = 0.61) and the amount of lengthening (β = 0.0023; p = 0.99). Subgroup analysis did not reveal difference between different doses of botulinum toxin and single or multi-site study design. An analysis of two randomized controlled trials enrolling a total of 177 individuals demonstrated a limited effect of botulinum toxin in reducing postoperative pain (SMD, − 0.239; 95% CI, − 0.641 to 0.162, p = 0.24, I² = 37.6%), total adverse events (SMD, − 0.207; 95% CI, − 0.505 to 0.090, p = 0.17, I² = 0.0%), and infection of pin site (SMD, − 0.131; 95% CI, − 0.428 to 0.165, p = 0.39, I² = 0.0%). No botulinum toxin–related adverse events were reported.

Conclusions

The current evidence does not support the administration of botulinum toxin in patients who receive distraction osteogenesis of the lower limbs. However, we were unable to draw decisive conclusions because of the limitations of our meta-analysis. Future well-designed, large-scale randomized controlled trials are necessary to confirm our conclusions.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12891-022-05175-2.