Apoptosis of endplate chondrocytes in post-laminectomy cervical kyphotic deformity

Purpose

The present study was performed to establish an animal model of cervical kyphosis after laminectomy (C2–C5), and to determine the role of endplate chondrocytes apoptosis in cervical kyphosis after laminectomy.

Methods

Twenty-four 3-month-old sheep were randomly divided into two groups: the laminectomy group (n = 12), and the control group (n = 12). The cervical spine alignment was evaluated on a lateral cervical spine X-ray using Harrison’s posterior tangent method before surgery and at follow-up. Cartilaginous endplate chondrocyte apoptosis was confirmed using transmission electron microscopy and terminal deoxyribonucleotidyl transferase (TdT)-mediated dUTP nick-end labelling.

Results

The mean preoperative cervical curvature (C2–5) in the surgery group was −15.8°. The cervical curvature was 19.1° at 3 months post-operation and decreased to 20.2° at the final follow-up postoperatively. The cervical curvature was significantly decreased in the laminectomy group compared with the control group at the last follow-up (P < 0.001), which was a direct indication of kyphotic change. The incidence of apoptotic cells in the surgery group was significantly higher at the 3- and 6-month follow-up than the incidence in the control group.

Conclusions

The frequency of endplate chondrocyte apoptosis in the laminectomy group was significantly higher than in the control group, indicating that chondrocyte apoptosis may play a pivotal role in the progress of post-laminectomy cervical kyphosis.     

Apical vertebral derotation in the posterior treatment of adolescent idiopathic scoliosis: myth or reality?

Introduction

Direct apical vertebral rotation represents an important goal of posterior surgery for thoracic adolescent idiopathic scoliosis (AIS), so as to obtain a better cosmetic effect and to avoid posterior thoracoplasty. However, the real effectiveness in correction of vertebral rotation, using posterior only procedures, is still open to debate. The aim of the present study is to compare the correction of axial apical rotation obtained with direct rotation procedure versus simple concave rod rotation, in patients treated by posterior fusion for thoracic AIS using pedicle screw-only construct.

Materials and methods

A retrospective review was performed on a total of 62 consecutive patients (one single institution, three different surgeons) affected by AIS, who had undergone a posterior spinal fusion with pedicle screw-only instrumentation between January 2005 and April 2008 at the reference center. All cases presented a main thoracic curve (Lenke type 1 and 2). The angle of rotation (RAsag) of the apical vertebra was measured from the preoperative and last follow-up axial CT. According to the derotation procedure, two groups were identified: a direct vertebral rotation group (DR group; n = 32 patients) and a simple concave rod rotation group (No-DR group; n = 30 patients). There were no statistical differences between the two groups, in terms of age, Risser’s sign, curve patterns, Cobb main thoracic (MT) curve magnitude and flexibility, extension of fusion, offset measurements on the coronal plane and sagittal preoperative contour.

Results

All 62 patients were reviewed at an average follow-up of 3.7 years (range 2.5–4.2 years). The DR group compared to the No-DR group showed a significantly better final correction of apical vertebral rotation (DR 63.4 % vs. No-DR 14.8 %; p < 0.05) and a greater final correction (61.3 vs. 52.4 %; p < 0.05) with better maintenance of the initial correction (−1.7° vs. −1.9°; ns) of the main thoracic curve. Concerning the coronal balance, there was the same aforementioned trend of better results in the DR group, with less final apical MT vertebra translation (DR 2.2 cm vs. No-DR 4.1 cm), greater overall change (preop-final) of lower instrumented vertebra (LIV) coronal tilt (−14.9° vs. −11.1°; p < 0.05); the final global coronal balance (C7–S1) resulted quite better in DR group, but without a significant difference. The T5–T12 kyphosis angle was quite similar in both group before surgery (DR 16.8° vs. No-DR 17.5°) and was little lower at final follow-up evaluation in direct vertebral rotation group (14.5° vs. 16.5°). The T10–L2 sagittal alignment angle was similar in each group before surgery (12.5° in DR vs. 11.8° in No-DR), and at the latest follow-up averaged 5.3° versus 8.2°, respectively. Lumbar lordosis was similar in each group before surgery (DR −42° vs. No-DR −44.1°) and at the final follow-up evaluation (−45.9° vs. −43.2°). At the latest follow-up, SRS-30 and SF-36 findings were similar between the two groups. The complication rate was higher in the simple concave rod rotation group (13.3 vs. 9.3 %), related in two cases to thoracoplasty, which was never utilized in direct rotation patients.

Conclusions

The direct vertebral rotation obtained significantly better final results, when compared to simple concave rod rotation, both concerning correction of apical vertebral rotation and magnitude of MT curve. On the other hand, the DR group presented a little reduction in T5–T12 kyphosis at follow-up, in comparison with concave rod rotation procedure. Both procedures were found to be satisfying from patients’ perspective. Nevertheless overall complication rate was higher in the simple concave rod rotation group, related mainly to thoracoplasty (2 cases), which was never necessary in direct rotation patients.     

Does atlantoaxial dislocation influence the subaxial cervical spine?

Introduction

Previous studies have reported that the alignments of the occipital-cervical and subaxial spine were closely interrelated in asymptomatic individuals; however, none have focused on a population with atlantoaxial dislocation.

Material and methods

From 2007 to 2011, 298 patients with atlantoaxial dislocation and atlas occipitalization were studied. Angles formed between Occiput-C2 and C2–C7 were measured. The relationship between the alignment of the occipital-cervical junction and the subaxial cervical spine was evaluated.

Results

The range of values for the angles measured was as followed: the Occiput-C2 angles were −35.2° to 44.8°, and the C2–C7 angles were −17.4° to 77.8°. Statistically significant negative correlations were observed between the Occiput-C2 and C2–C7 angles.

Conclusion

Anterior dislocations of the atlas are associated with diminished lordosis or even kyphosis of the occipital-cervical junction, and result in compensatory hyperlordosis of the subaxial cervical spine, collectively presenting as a “swan neck” deformity. Atlantoaxial dislocation may influence the global cervical alignment.     

Body composition modifications in people with chronic spinal cord injury after supervised physical activity

Background

Quantification of body composition variables is important for planning of better activities in relation to individuals with spinal cord injury (SCI).

Objectives

(1) To evaluate changes in body composition in patients with SCI after a supervised physical activity process; (2) To correlate total body fat with time since injury.

Design

Pre-post intervention.

Setting

Sarah Rehabilitation Hospital Network, Brazil.

Participants

Fifty-three men with SCI aged 18–52 years with duration of injury >3 years.

Interventions

The subjects were divided into three groups: tetraplegia (TT) (C5–C8), high paraplegia (HP) (T1–T6), and low paraplegia (LP) (T7–L2). Body composition was estimated in the first and last weeks of hospitalization.

Outcome measures

Body weight (kg), skinfolds sum (mm), absolute (kg), and relative (%) fat and lean body mass.

Results

Body weight increased in TT and decreased in HP (0.8 kg, 95%CI 0.1–1.5; and −1.0 kg, 95%CI −2.0 to 0.0, respectively; P < 0.05). Skinfolds sum decreased only in HP (−13.1 mm, 95%CI −20.7 to −5.5; P < 0.05). Absolute and relative body fat decreased significantly in the paraplegia groups. Lean body mass (LBM) percentage increased significantly in the paraplegia groups. Absolute LBM increased in TT and LP (0.8 kg, 95%CI 0.3–1.3; and 1.3 kg, 95%CI 0.8 to 1.8, respectively; P < 0.05). There was no correlation between time since injury and skinfolds sum for the three groups (P < 0.05).

Conclusion

TT, HP, and LP demonstrated favorable changes in body composition after 29 days of supervised physical activity. However, these changes were different in direction and magnitude.     

Contemporary femoral designs in total knee arthroplasty: effects on the patello-femoral congruence

Purpose

The objective of this study was to evaluate the radiological and clinical correlations between implant design and patellar positioning in patients who underwent TKA utilizing femoral implants with modern designs.

Methods

Thirty consecutive PFC PS Sigma TKAs, characterized by a new prolonged anterior flange and a “smoother” trochlea, were prospectively reviewed. All patellae were replaced. All patients were evaluated pre-operatively and prospectively at two years follow-up both clinically according to the Knee Society score as well as radiographically. This included computed tomography (CT); patellar tilt, patellar conformity angle, patellar lateralization, and femoral component external-rotation in relation to the clinical trans-epicondylar axis.

Results

Average patellar tilt at follow-up was 3° (±7.5°) with respect to a pre-operative 18.5° (±8.5°). Average patellar congruence angle at follow-up was −3° (range, −11° to +9°) with respect to a pre-operative 10.3° (range, + 1.5° to 25.5°). Average lateralization index at follow-up was 2.7 mm (range, −3.4 mm to +7.1 mm) with respect to a pre-operative 12.2 mm (± 4.8 mm). Femoral component positioning related to the trans-epicondylar axis showed an external rotation of 2.80° (± 2.10°) at follow-up with respect to 5.7° (± 1.80°). Clinically, two (6.6%) patients reported patello-femoral complications related to imperfections in the surgical technique more than the implant''s design.

Conclusions

This study highlighted that modern femoral designs in TKA allow for a correct reproducibility of a normal patello-femoral conformity. Strict surgical principles are paramount to avoid patello-femoral complications even when modern implants are used.     

Development of the tibiofemoral angle in a cohort of Nigerian children during the first 3 years of life

Purpose

Findings from cross-sectional studies of knee angle development in Nigerian children vary in values and in the age at which the varus angle changes to the valgus angle. This study was conducted to describe knee angle development and to determine the age when the knee angle changes from the varus to the valgus angle.

Methods

This was a longitudinal survey of 152 Nigerian children recruited within 3 weeks of life and followed up monthly until age 3 years. Their knee angle was measured using clinical methods.

Results

The mean tibio-femoral/varus knee angle (13.2 ± 3.8°) at birth–3 weeks of life decreased sharply to 5.6 ± 0.7° at 9 months, increased slightly to 6.3 ± 1.1° at 13 months, and then decreased again up to age 18 months (0.3 ± 2.1°). The mean valgus knee angle increased from −2.4 ± 2.5° at 19 months of life to −8.5 ± 2.5° at 27 months and then decreased to −7.7 ± 2.2° at 36 months. Intercondylar/intermalleolar distances (ICD/IMD) showed a similar pattern, changing from an extreme varus knee (ICD) at birth–3 weeks of life (2.5 ± 0.7 cm), decreasing to 0.6 ± 0.2 cm at 9 months, increasing to 0.8 ± 0.5 cm at 12 months, and decreasing to 0.1 ± 0.4 cm at 15 months. The mean IMD increased from −0.1 ± 0.8 cm at 16 months of life to −2.0 ± 1.5 cm at 29 months and then decreased up to 36 months. Our tri-modal analysis showed that the transition from the varus to the valgus angle was between 18 and 19 months.

Conclusion

Our findings suggest that the developmental pattern of the knee angle in Nigerian children is at maximal varus at birth, neutral at 18 months of life, and valgus at 19 months, with the valgus angle continuing to increase up to 36 months.     

Biomechanical study of the spinal cord in thoracic ossification of the posterior longitudinal ligament

Background

Ossification of the posterior longitudinal ligament (OPLL) in the thoracic spine produces myelopathy. This is often progressive and is not affected by conservative treatment. Therefore, decompressive surgery is usually chosen.

Objective

To conduct a stress analysis of the thoracic OPLL.

Methods

The three-dimensional finite element spinal cord model was established. We used local ossification angle (LOA) for the degree of compression of spinal cord. LOA was the medial angle at the intersection between a line from the superior posterior margin at the cranial vertebral body of maximum OPLL to the top of OPLL with beak type, and a line from the lower posterior margin at the caudal vertebral body of the maximum OPLL to the top of OPLL with beak type. LOA 20°, LOA 25°, and LOA 30° compression was applied to the spinal cord in a preoperative model, the posterior decompressive model, and a model for the development of kyphosis.

Results

In a preoperative model, at more than LOA 20° compression, high stress distributions in the spinal cord were observed. In a posterior decompressive model, the stresses were lower than in the preoperative model. In the model for development of kyphosis, high-stress distributions were observed in the spinal cord at more than LOA 20° compression.

Conclusions

Posterior decompression was an effective operative method. However, when the preoperative LOA is more than 20°, it is very likely that symptoms will worsen. If operation is performed at greater than LOA 20°, then correction of kyphosis by fixation of instruments or by forward decompression should be considered.     

Lumbopelvic motion during seated hip flexion in subjects with low-back pain accompanying limited hip flexion

Purpose

Limited hip flexion may lead to a poor lumbopelvic motion during seated active hip flexion in people with low-back pain (LBP). The purpose of this study was to compare lumbopelvic motion during seated hip flexion between subjects with and without LBP accompanying limited hip flexion.

Methods

Fifteen patients with LBP accompanying limited hip flexion and 16 healthy subjects were recruited. The subjects performed seated hip flexion with the dominant leg three times. A three-dimensional motion-analysis system was used to measure lumbopelvic motion during seated hip flexion.

Results

During seated active hip flexion, the angle of hip flexion was significantly lower in patients with LBP accompanying limited hip flexion (17.4 ± 4.4 in the LBP group, 20.8 ± 2.6 in the healthy group; t = 2.63, p = 0.014). The angle of the lumbar flexion (4.8 ± 2.2 in the LBP group, 2.6 ± 2.0 in the healthy group; t = −2.96, p = 0.006) and posterior pelvic tilting (5.0 ± 2.6 in the LBP group, 2.9 ± 2.0 in the healthy group; t = 2.48 p = 0.019), however, were significantly greater in patients with this condition.

Conclusions

The results of this study suggest that limited hip flexion in LBP can contribute to excessive lumbar flexion and posterior pelvic tilting during hip flexion in the sitting position. Further studies are required to confirm whether improving the hip flexion range of motion can reduce excessive lumbar flexion in patients with LBP accompanying limited hip flexion.     

Surgical treatment of Scheuermann’s kyphosis using a combined antero-posterior strategy and pedicle screw constructs: efficacy,radiographic and clinical outcomes in 111 cases

Introduction

There is sparse literature on how best to correct Scheuermann’s kyphosis (SK). The efficacy of a combined strategy with anterior release and posterior fusion (AR/PSF) with regard to correction rate and outcome is yet to be determined.

Materials and methods

A review of a consecutive series of SK patients treated with AR/PSF using pedicle screw–rod systems was performed. Assessment of demographics, complications, surgical parameters and radiographs including flexibility and correction measures, proximal junctional kyphosis angle (JKA + 1) and spino-pelvic parameters was performed, focusing on the impact of curve flexibility on correction and clinical outcomes.

Results

111 patients were eligible with a mean age of 23 years, follow-up of 24 months and an average of eight levels fused. Cobb angle at fusion level was 68° preoperatively and 37° postoperatively. Flexibility on traction films was 34 % and correction rate 47 %. Postoperative and follow-up Cobb angles were highly correlated with preoperative bending films (r = 0.7, p < 0.05). Screw density rate was 87 %, with increased correction with higher screw density (p < 0.001, r = 0.4). Patients with an increased junctional kyphosis angle (JKA + 1) were at higher risk of revision surgery (p = 0.049). 22 patients sustained complication, and 21 patients had revision surgery. 42 patients with ≥24 months follow-up were assessed for clinical outcomes (follow-up rate for clinical measures was 38 %). This subgroup showed no significant differences regarding baseline parameters as compared to the whole group. Median approach-related morbidity (ArM) was 8.0 %, SRS-sum score was 4.0, and ODI was 4 %. There was a significant negative correlation between the SRS-24 self-image scores and the number of segments fused (r = −0.5, p < 0.05). Patients with additional surgery had decreased clinical outcomes (SRS-24 scores, p = 0.004, ArM, p = 0.0008, and ODI, p = 0.0004).

Conclusion

The study highlighted that AR/PSF is an efficient strategy providing reliable results in a large single-center series. Results confirmed that flexibility was the decisive measure when comparing surgical outcomes with different treatment strategies. Findings indicated that changes at the proximal junctional level were impacted by individual spino-pelvic morphology and determined by the individually predetermined thoracolumbar curvature and sagittal balance. Results stressed that in SK correction, reconstruction of a physiologic alignment is decisive to achieving good clinical outcomes and avoiding complications.     

Correlating preoperative imaging with intraoperative fluoroscopy in iliosacral screw placement

Background

Percutaneous iliosacral screw placement can successfully stabilize unstable posterior pelvic ring injuries. Intraoperative fluoroscopic imaging is a vital component needed in safely placing iliosacral screws. Obtaining and appropriately interpreting fluoroscopic views can be challenging in certain clinical scenarios. We report on a series of patients to demonstrate how preoperative computed tomography (CT) imaging can be used to anticipate the appropriate intraoperative inlet and outlet fluoroscopic views.

Materials and methods

24 patients were retrospectively identified with unstable pelvic ring injuries requiring operative fixation using percutaneous iliosacral screws. Utilizing the sagittal reconstructions of the preoperative CT scans, anticipated inlet and outlet angle measurements were calculated. The operative reports were reviewed to determine the angles used intraoperatively. Postoperative CT scans were reviewed for repeat measurements and to determine the location and safety of each screw.

Results

Preoperative CT scans showed an average inlet of 20.5° (7°–37°) and an average outlet of 42.8° (30°–59°). Intraoperative views showed an average inlet of 24.9° (12°–38°) and an average outlet of 42.4° (29°–52°). Postoperative CT scans showed an average inlet of 19.4° (8°–31°) and an average outlet of 43.2° (31°–56°). The average difference from preoperative to intraoperative was 4.4° (−21° to 5°) for the inlet and 0.45° (−9° to 7°) for the outlet. The average difference between the preoperative and postoperative CT was 2.04° (0°–6°) for the inlet and 2.54° (0°–7°) for the outlet.

Conclusion

There is significant anatomic variation of the posterior pelvic ring. The preoperative CT sagittal reconstruction images allow for appropriate preoperative planning for anticipated intraoperative fluoroscopic inlet and outlet views within 5°. Having knowledge of the desired intraoperative views preoperatively prepares the surgeon, aids in efficiently obtaining correct intraoperative views, and ultimately assists in safe iliosacral screw placement.

Level of evidence

IV, Retrospective case series.     

The deviation of the mechanical leg axis correlates with an increased hip alpha angle and could be a predictor of femoroacetabular impingement

Purpose

This study was designed to evaluate whether the mechanical axis deviation (MAD) of the leg correlates with an increased hip alpha angle as described by Nötzli, which is associated with femoroacetabular impingement (FAI).

Methods

In a retrospective analysis, standing full-length anteroposterior radiographs were analysed in patients who suffered from symptomatic leg alignment. The study included 85 radiographs of 80 patients with an average age of 43.11 years (range 18–60 years). Five patients underwent a bilateral long-leg X-ray examination. All radiographs were transferred as Digital Imaging and Communications in Medicine data files from the Picture Archiving and Communications System into the OrthoPlanner software version 2.3.2. The radiographs were measured by one orthopaedic surgeon and one independent radiologist.

Results

The mean value of the alpha angle of Nötzli was 61.43° (49.07–74.04°). A total of 57 (67 %) radiographs showed a varus deviation, 25 (29.5 %) had a valgus malalignment and three (3.5 %) a straight leg axis. Of 82 radiographs, 40 (48.8 %) had a moderate axis deviation with a MAD <15 or > − 15 mm and a mean alpha angle of 57.81°, and 42 (51.2 %) with extended axis deviation of a MAD > 15 or < − 15 mm had a mean alpha angle of 62.93°; 40 (95.2 %) of these 42 showed an alpha angle > 55°. The alpha angle was significantly increased in extended axis deviation compared to moderate axis deviation (P = 0.001).

Conclusions

This study confirmed that increased alpha angles were found significantly at higher degrees of axis deviation on the full-length radiograph. In cases of a MAD >15 or < − 15 mm and symptomatic coxalgia, diagnostic tests must be pursued for FAI.     

Relevance of expandable titanium cage for the treatment of cervical spondylotic myelopathy

Background

In patients with cervical spondylotic myelopathy, ventral disease and loss of physiological cervical lordosis are indications for anterior approach. As bone graft and titanium cage present many drawbacks, expandable titanium cage has been recently introduced for this indication. The authors present the clinical and radiological outcomes in patients undergoing the placement of an expandable cage in the treatment of spondylotic myelopathy with straight or kyphotic cervical spine alignment.

Methods

This was a retrospective review of prospectively collected data. A total of 26 patients underwent cervical corpectomy and reconstruction using an expandable titanium cage and anterior plate between 2005 and 2008. Pain and functional disability were measured using VAS and mJOA preoperatively and at 3 months, 6 months, 1 year and 2 years. Kyphosis was measured using lateral radiographs at the same points of follow-up. Fusion was evaluated on flexion–extension radiographs at 2 years.

Results

The mean VAS improved from 4.2 to 1.7 and the mean mJOA increased from 12.85 to 16.04 at 2 years postoperatively (p < 0.05). The mean kyphosis angle decreased from 17° to 2° at the last follow-up (p < 0.05). The fusion rate was 100 % at 2 years. Three complications were reported including a transient dysphagia, an epidural hematoma and an early hardware migration.

Conclusion

Expandable titanium cage is an effective device, which achieves good clinical and radiological outcomes at a minimum 2-year follow-up.     

Retrograde dynamic locked nailing for valgus knee correction: a revised technique

Purpose

Traditionally, valgus knee deformity is predominately corrected by stabilisation with a plate inserted via the medial approach to the supracondylar region of the femur. However, this technique is unfavourable from both a biomechanical and a biological point of view. A revised retrograde dynamic locked nailing was developed to improve correction of this defect.

Method

Forty-one knees with valgus deformity (average tibiofemoral angle, 22°; range, 16–29°) in 25 adult patients were treated by oblique femoral supracondylar varus osteotomy and stabilised with retrograde dynamic locked nails. Postoperatively, early ambulation with protected weight bearing and range of motion knee exercises were encouraged.

Result

Thirty-five knees of 21 patients were followed-up for an average of 2.6 years (range, 1.1–4.5 years). All osteotomy sites healed with an average union period of 3.4 months (range, 2.5–5.0 months). There were no significant complications. At the latest follow-up, the average tibiofemoral angle was 7.1° valgus (range, 4–10° valgus). For all of the knees, the outcomes were satisfactory (p < 0.001).

Conclusion

The technique described here may be a feasible alternative for correction of valgus knee deformity. The advantages of this technique include the use of a biomechanically more appropriate method, a minimal complication rate and a high rate of satisfactory outcomes.     

Radiographic quantification of dynamic hip screw migration

Purpose

This study aimed to propose a technique to quantify dynamic hip screw (DHS®) migration on serial anteroposterior (AP) radiographs by accounting for femoral rotation and flexion.

Methods

Femoral rotation and flexion were estimated using radiographic projections of the DHS® plate thickness and length, respectively. The method accuracy was evaluated using a synthetic femur fixed with a DHS® and positioned at pre-defined rotation and flexion settings. Standardised measurements of DHS® migration were trigonometrically adjusted for femoral rotation and flexion, and compared with unadjusted estimates in 34 patients.

Results

The mean difference between the estimated and true femoral rotation and flexion values was 1.3° (95 % CI 0.9–1.7°) and −3.0° (95 % CI – 4.2° to −1.9°), respectively. Adjusted measurements of DHS® migration were significantly larger than unadjusted measurements (p = 0.045).

Conclusion

The presented method allows quantification of DHS® migration with adequate bias correction due to femoral rotation and flexion.

Electronic supplementary material

The online version of this article (doi:10.1007/s00264-013-2146-4) contains supplementary material, which is available to authorised users.     

Hidden discoligamentous instability in cervical spine injuries: can quantitative motion analysis improve detection?

Purpose

Recent literature shows that occult discoligamentous injuries still remain difficult to diagnose in the first instance. Thresholds as indicators for discoligamentous segmental instability were previously defined. But, since supine radiodiagnostic is prone to spontaneous reduction of a displaced injury, and even some highly unstable injuries reveal only slight radiographic displacement, these criteria might mislead in the traumatized patient. A highly accurate radiographic instrument to assess segmental motion is the computer-assisted quantitative motion analysis (QMA). The aim was to evaluate the applicability of the QMA in the setting of a traumatized patient.

Methods

Review of 154 patients with unstable cervical injuries C3–7. Seventeen patients (male/female: 1:5, age: 44.6 years) had history of initially hidden discoligamentous injuries without signs of neurologic impairment. Initial radiographs did not fulfill instability criteria by conventional analysis. Instability was identified by late subluxation/dislocation, persisting/increasing neck pain, and/or scheduled follow-up. For 16 patients plain lateral radiographs were subjected to QMA. QMA data derived were compared with normative data of 140 asymptomatic volunteers from an institutional database.

Results

Data analysis of measurements revealed mean spondylolisthesis of −1.0 mm (−3.7 to +3.4 mm), for segmental rotational angle mean angulation of −0.9° (−11.1° to +17.7°). Analysis of these figures indicated positive instability thresholds in 5 patients (31.3 %). Analysis of center of rotation (COR)-shifts was only accomplishable completely in 3/16 patients due to limited motion or inadequacy of radiographs. Two of these patients (12.5 %) showed a suspect shift of the COR.

Conclusions

Our data show a high rate of false negative results in cases of hidden discoligamentous injuries by using conventional radiographic analysis as well as QMA in plain lateral radiographs in a trauma setting. Despite the technical possibilities in a modern trauma center, our data and recent literature indicate a thorough clinical and radiographic follow-up of patients with cervical symptoms to avoid secondary complications from missed cervical spine injuries.     

Crossed pinning in paediatric supracondylar humerus fractures: a retrospective cohort analysis

Purpose

The aim of this study was to analyse the management of displaced paediatric supracondylar humerus fractures at our Level I Trauma Centre and to determine clinical and radiographic long-term results following operative treatment.

Methods

Clinical and radiological results of 78 paediatric patients (29 female, 49 male; mean age 5.1 years) with supracondylar humerus fractures, treated from 1992 to 2004, were evaluated. Gartland’s classification yielded 32 type II, 44 type III and further two flexion injuries. In all patients the follow-up period exceeded 12 months. Assessment after an average of 8.1 years (1.1–19.5) included neurovascular examination, Flynn’s criteria (elbow function and carrying angle), pain, complications (infections, growth disturbances or iatrogenic nerve injuries) and measurement of the humeroulnar angle.

Results

According to Flynn’s criteria 73 patients (93.5 %) had a satisfactory outcome, while five (6.4 %) were graded as unsatisfactory (two due to cubitus varus and three because of limited elbow motion). The visual analogue scale (VAS) score averaged 0 (range 0–1) and the mean carrying angle measured 8.4° (−8 to 20°), compared to 10.8° on the contralateral side (2–20°). Injury-related complications yielded absent pulses in four (5.1 %), five (6.4 %) primary median, two (2.6 %) primary radial and one (1.3 %) primary ulnar nerve injury. Treatment-related complications included a secondary displacement and one iatrogenic radial nerve palsy. Based on primary nerve lesion as a dependent variable, statistical analysis showed that age had a significant influence revealing that older paediatric patients had a significantly higher risk (p = 0.02). Functional outcome as a dependent variable revealed an indirect proportion to the clinical carrying angle, achieving statistical significance (p < 0.01).

Conclusions

Crossed pinning in paediatric supracondylar humerus fractures is an effective method. Evaluation of the outcome in our study group demonstrated good results with the treatment approach described.