Influence of growth hormone treatment on radiographic indices of the spine: propensity-matched analysis.

BACKGROUND: We performed this study to investigate the influence of recombinant human growth hormone (rhGH) therapy on radiographic indices of the spine using propensity-matched analysis. METHODS: Patients with idiopathic short stature who had undergone both growth hormone therapy and whole-spine radiographs more than twice prior to 15 years of age were included in the patient group. Other patients who had undergone whole-spine radiographs more than twice prior to the same age during regular checkups for idiopathic scoliosis formed the control group. Propensity-matched analysis was performed to reduce the selection bias. The scoliosis Cobb angle, coronal balance, apical vertebral translation, apical rotation, and pelvic obliquity were measured from the radiographs taken at the periodic follow-ups. The rate of progression of the measurements was adjusted by multiple factors using a linear mixed model with sex as the fixed effect and age and each subject as the random effects. RESULTS: Using a propensity-matched analysis, 48 patients were finally included in both groups. The scoliosis Cobb angle increased by 1.0° (p < 0.001) per year in the patient group, whereas there was no significant annual change in the control group (p = 0.496). Female patients showed a greater scoliosis Cobb angle (1.8°, p = 0.039) compared with male patients. There was no significant difference between the patient and control groups in coronal balance (p = 0.264). Apical vertebral translation per year was increased by 1.2 mm (p < 0.001) in the patient group and 0.5 mm in the control group (p = 0.003). CONCLUSION: Radiographic examination revealed that growth hormone therapy for idiopathic short stature affected the progression of the scoliosis Cobb angle and apical vertebral translation on the coronal plane. Physicians should be aware that annual follow-up is required to evaluate the change in the curvature of the spine in patients undergoing rhGH treatment.

Development of a decellularization method to produce nerve allografts using less invasive detergents and hyper/hypotonic solutions.

BACKGROUND: Here, we describe a novel method of processing decellularized nerve grafts using osmotic effects of hypotonic and hypertonic solutions and Triton X-100 (a nonionic detergent) and CHAPS (an amphoteric detergent). MATERIALS AND METHODS: To evaluate decellularization, the devised method and Hudson's method were compared with respect to remaining cellular components (as assessed by H&E staining and S-100 immunoreactivity) and extracellular matrix structural integrity (as assessed by H&E staining and laminin immunoreactivity) by using rat sciatic nerves. In addition, a 1.5-cm sciatic nerve gap rat model was treated by implanting decellularized nerve grafts prepared using the devised method, Hudson's method, or an autograft to evaluate nerve regeneration. Nerve histomorphometry of distal stumps and wet muscle mass were evaluated at 12 weeks after implantation. RESULTS: The devised method produced outcomes similar to those of Hudson's method in terms of cellular component removal, but the devised method was significantly better in terms of ECM preservation. Histomorphometric study showed that the devised method produced significantly fewer nerve fiber and axonal densities than autografting, but much more than Hudson's method. The wet muscle mass of the devised method was also significantly lower than that of autografting, but much higher than that of Hudson's method. CONCLUSION: The described process for producing decellularized nerve grafts yielded better outcomes with respect to peripheral nerve regeneration than the established ionic detergent-based methods in a rat model. This study indicates that decellularized nerve grafts produced in this manner show favorable nerve regeneration used for bridging nerve gaps.

Changes in Clinical Symptoms, Functions, and the Median Nerve Cross-Sectional Area at the Carpal Tunnel Inlet after Open Carpal Tunnel Release.

BACKGROUND: The aim of this study was to investigate the relationship between clinical symptoms and cross-sectional area (CSA) of the median nerve at the carpal tunnel inlet before and after open carpal tunnel release (CTR). METHODS: Thirty-two patients (53 hands) that underwent open CTR for idiopathic carpal tunnel syndrome were prospectively enrolled. Median nerve CSA at the carpal tunnel inlet was measured preoperatively and at 2 and 12 weeks after CTR by high resolution ultrasonography. The Boston carpal tunnel questionnaire (BCTQ) was also completed at these times. RESULTS: BCTQ symptom (BCTQ-S) score was significantly improved at 2 weeks postoperatively, but BCTQ function (BCTQ-F) score and CSA were significantly improved at 12 weeks postoperatively. Preoperative CSA was significantly correlated with preoperative BCTQ-S and BCTQ-F scores but was not significantly correlated with postoperative BCTQ scores or postoperative changes in BCTQ scores. Postoperative median nerve CSA was not significantly correlated with postoperative BCTQ-S or BCTQ-F scores, and postoperative changes in median nerve CSA were not significantly correlated with postoperative changes in BCTQ-S or BCTQ-F scores. CONCLUSIONS: The study shows clinical symptoms resolve rapidly after open CTR, but median nerve swelling and clinical function take several months to recover. In addition, preoperative median nerve swelling might predict preoperative severities of clinical symptoms and functional disabilities. However, postoperative reductions in median nerve swelling were not found to reflect postoperative reductions in clinical symptoms or functional disabilities.

BMP6-Engineered MSCs Induce Vertebral Bone Repair in a Pig Model: A Pilot Study.

Osteoporotic patients, incapacitated due to vertebral compression fractures (VCF), suffer grave financial and clinical burden. Current clinical treatments focus on symptoms' management but do not combat the issue at the source. In this pilot study, allogeneic, porcine mesenchymal stem cells, overexpressing the BMP6 gene (MSC-BMP6), were suspended in fibrin gel and implanted into a vertebral defect to investigate their effect on bone regeneration in a clinically relevant, large animal pig model. To check the effect of the BMP6-modified cells on bone regeneration, a fibrin gel only construct was used for comparison. Bone healing was evaluated in vivo at 6 and 12 weeks and ex vivo at 6 months. In vivo CT showed bone regeneration within 6 weeks of implantation in the MSC-BMP6 group while only minor bone formation was seen in the defect site of the control group. After 6 months, ex vivo analysis demonstrated enhanced bone regeneration in the BMP6-MSC group, as compared to control. This preclinical study presents an innovative, potentially minimally invasive, technique that can be used to induce bone regeneration using allogeneic gene modified MSCs and therefore revolutionize current treatment of challenging conditions, such as osteoporosis-related VCFs.

PTH Induces Systemically Administered Mesenchymal Stem Cells to Migrate to and Regenerate Spine Injuries.

Osteoporosis affects more than 200 million people worldwide leading to more than 2 million fractures in the United States alone. Unfortunately, surgical treatment is limited in patients with low bone mass. Parathyroid hormone (PTH) was shown to induce fracture repair in animals by activating mesenchymal stem cells (MSCs). However, it would be less effective in patients with fewer and/or dysfunctional MSCs due to aging and comorbidities. To address this, we evaluated the efficacy of combination i.v. MSC and PTH therapy versus monotherapy and untreated controls, in a rat model of osteoporotic vertebral bone defects. The results demonstrated that combination therapy significantly increased new bone formation versus monotherapies and no treatment by 2 weeks (P < 0.05). Mechanistically, we found that PTH significantly enhanced MSC migration to the lumbar region, where the MSCs differentiated into bone-forming cells. Finally, we used allogeneic porcine MSCs and observed similar findings in a clinically relevant minipig model of vertebral defects. Collectively, these results demonstrate that in addition to its anabolic effects, PTH functions as an adjuvant to i.v. MSC therapy by enhancing migration to heal bone loss. This systemic approach could be attractive for various fragility fractures, especially using allogeneic cells that do not require invasive tissue harvest.

Should an ulnar styloid fracture be fixed following volar plate fixation of a distal radial fracture?

BACKGROUND: Ulnar styloid fractures often occur in association with distal radial fractures. The purpose of this study was to determine whether an associated ulnar styloid fracture following stable fixation of a distal radial fracture has any effect on wrist function or on the development of chronic distal radioulnar joint instability. METHODS: One hundred and thirty-eight consecutive patients who underwent surgical treatment of an unstable distal radial fracture were included in this study. During surgery, none of the accompanying ulnar styloid fractures were internally fixed. Patients were divided into nonfracture, nonbase fracture, and base fracture groups, on the basis of the location of the ulnar styloid fracture, and into nonfracture, minimally displaced (< or =2 mm), and considerably displaced (>2 mm) groups, according to the amount of ulnar styloid fracture displacement at the time of injury. Postoperative evaluation included measurement of grip strength and wrist range of motion; calculation of the modified Mayo wrist score and Disabilities of the Arm, Shoulder and Hand score; as well as testing for instability of the distal radioulnar joint at a mean of nineteen months postoperatively. RESULTS: Ulnar styloid fractures were present in seventy-six (55%) of the 138 patients. Forty-seven (62%) involved the nonbase portion of the ulnar styloid and twenty-nine (38%) involved the base of the ulnar styloid. Thirty-four (45%) were minimally displaced, and forty-two (55%) were considerably (>2 mm) displaced. We did not find a significant relationship between wrist functional outcomes and ulnar styloid fracture level or the amount of displacement. Chronic instability of the distal radioulnar joint occurred in two wrists (1.4%). CONCLUSIONS: An accompanying ulnar styloid fracture in patients with stable fixation of a distal radial fracture has no apparent adverse effect on wrist function or stability of the distal radioulnar joint.

Stress fracture of the pelvic wing-sacrum after long-level lumbosacral fusion: a case report.

STUDY DESIGN: A case report of transverse stress fracture of the pelvic wing-sacrum after long-level lumbosacral fusion. OBJECTIVE: To report this rare complication of long-level lumbosacral fusion. SUMMARY OF BACKGROUND DATA: There are a number of well-described complications of instrumented lumbosacral fusion, including delayed stress fracture of the pelvis. A bilateral pelvic wing-sacrum transverse stress fracture after long-level lumbosacral fusion has not been previously reported to our knowledge. METHODS: Radiography and computed tomography were used to confirm the diagnosis. Long lumbosacral fusion and a pelvic wing-sacrum fracture were shown. RESULTS: A 48-year-old woman underwent several revision spinal surgeries for collapse or instability occurring at the adjacent levels. She presented with low back and bilateral buttock pain with slow progression after last surgery. A bilateral transverse pelvic wing-sacrum stress fracture was found on plain radiographs 7 months later. CONCLUSIONS: Stress fracture of bilateral pelvic wing-sacrum can occur as a potential source of late pain after long fusions of the lumbosacral spine. A better understanding of the related biomechanical forces and preoperative risk factors may identify patients at risk and may aid in surgical planning. There are few reports of pelvic stress fracture as a complication of lumbosacral fusion, and it is typically described as a late occurrence. We present the occurrence of a bilateral pelvic wing-sacrum transverse stress fracture, not previously discussed to our knowledge.