Comparison of the Effects of Proximal Humeral Internal Locking System (PHILOS) Alone and PHILOS Combined with Fibular Allograft in the Treatment of Neer Three- or Four-part Proximal Humerus Fractures in the Elderly.

OBJECTIVE: To compare and analyze the clinical outcomes of the proximal humeral internal locking system (PHILOS) alone and the PHILOS combined with fibular allograft in the treatment of Neer three- and four-part proximal humerus fractures (PHF) in the elderly. METHODS: From January 2014 to January 2018, a total of 42 elderly patients with Neer three- or four-part PHF admitted to our hospital were randomly divided into observation group and control group, with 21 patients in each group. The observation group was treated with the PHILOS combined with fibular allograft. The control group was treated with the PHILOS alone. Perioperative parameters and fracture classification were recorded in the two groups. Function results were assessed by Visual Analog Scale (VAS), Constant-Murley score (CMS), American Shoulder and Elbow Surgeons (ASES) score, and the Disability of Arm-Shoulder-Hand (DASH) score. Radiological results were evaluated using the neck-shaft angle (NSA) and humeral head height (HHH), and complications were also recorded in each group. RESULTS: There were no significant differences between the two groups in terms of preoperative status, age, gender, cause of trauma, fracture site, and fracture classification. The average follow-up time was 12 months. At the last follow-up, the VAS and DASH observation groups were lower than the control group, and there was significant difference between the two groups (P < 0.05). The CMS and ASES were higher in the observation group than the control group, and there was significant difference between the two groups (P < 0.05). The mean difference in the NSA and HHH were lower in the observation group than the control group, and there was a significant difference between the two groups (P < 0.05). There was one postoperative complication in the observation group, which was humeral head avascular necrosis (AVN). There were seven postoperative complications in the control group, including three cases of humeral head collapse and three cases of screw cutout and one case of humeral head AVN. The incidence of postoperative complications in the observation group was significantly lower than the control group (P < 0.05), there was a significant difference between the two groups. CONCLUSIONS: For Neer three- or four-part PHF in the elderly patients, PHILOS fixation with fibular allograft shows satisfactory short-term results with respect to humeral head support and maintenance of reduction, and may reduce the incidence of complications associated with fixation using a PHILOS alone.

[Case control study on Zero-profile intervertebral fusion system and conventional cage-plate intervertebral fusion system for the treatment of multi-segment cervical spondylosis].

OBJECTIVE: To explore the clinical effect in the near future between Zero-profile intervertebral fusion system (Zero-P) and conventional cage-plate intervertebral fusion system (CCP) for the multi-segment(>=2 segments) cervical spondylosis. METHODS: Forty-two patients with cervical spondylosis who underwent multi-segment decompression of the cervical spine from October 2012 to October 2017 were selected as subjects. Zero-P was applied in 21 patients (Zero-P group) and CCP was applied in 21 patients(CCP group). The general condition and perioperative parameters of all the patients were recorded. VAS, JOA scores and incidence of dysphagia were observed before and after operation. The prevertebral soft tissue thickness was measured at 1 week, 1 month after operation and at the last follow-up. At the same time, the Cobb angle of the functional unit of the fusion segments was measured, and the overall curvature change of the cervical vertebra was observed. The clinical efficacy was reviewed at 1 week, 1, 3, 12 months after surgery, and the AP and lateral cervical X-rays were reviewed to evaluate the internal fixation effect. RESULTS: There were no significant differences in age, gender, duration of disease, surgical segment, follow-up time and hospitalization time between two groups(P>0.05). The length of the surgical incision, intraoperative blood loss, operation time, postoperative drainage volume in the Zero-P group were(4.37±0.72) cm, (50.9±7.98)ml, (84.4±8.18) min, (76.2±10.13) ml, respectively, and those in CCP group were (6.50±0.71) cm, (108.6±9.25) ml, (118.6±8.55) min, (130.1±9.42) ml, respectively. There were signigicant differences in above items between two groups(P<0.05). There were no significant difference in the VAS and JOA improvement rate between two groups at the last follow-up (P>0.05). There was no significant difference in the overall physiological curvature of the cervical vertebra between two groups (P>0.05). The prevertebral soft tissue thickness at 1 week, 1 month after operation, final follow-up respectively was(11.6±1.9), (9.8±1.4), (9.5±1.6) mm in Zero-P group, and in CCP group those were(12.5±2.6), (11.1±2.4), (11.0±1.9) mm, respectively. There were significant differences in each time point between two groups(P<0.05). At the last follow-up, no complication of dysphagia was found in Zero-P group, and three patients had dysphagia in CCP group, with a statistically significant difference between two groups (P<0.05). CONCLUSIONS: Multiple segmental decompression fusion to treat cervical spondylosis, regardless of the traditional CCP system or new Zero-P system are effective methods, but the Zero-P system has advantages of small surgical incision, short operation time, less intraoperative bleeding, convenient operation, better recovery of prevertebral soft tissue swelling, and lower possibility of postoperative dysphagia.

Application of 3D printing rapid prototyping-assisted percutaneous fixation in the treatment of intertrochanteric fracture.

The aim of the present study was to investigate the application of 3D printing (3DP) rapid prototyping (RP) technique-assisted percutaneous fixation in the treatment of femoral intertrochanteric fracture (ITF) using proximal femoral nail anti-rotation (PFNA). A total of 39 patients with unstable ITF were included in the current study. Patients were divided into two groups: 19 patients were examined using computed tomography scanning and underwent PFNA with SDP-RP whereas the other 20 patients underwent conventional PFNA treatment. Anatomical data were converted from the Digital Imaging and Communications in Medicine format to the stereolithography format using M3D software. The 3DP-RP model was established using the fused deposition modeling technique and the length and diameter of the main screw blade was measured during the simulation. The postoperative femoral neck-shaft angle (NSA), surgery duration, intraoperative and postoperative blood loss, and the duration of hospital stay were recorded and compared with the corresponding values in conventional surgery. No significant differences were observed in mean PFNA size between the implants used and the preoperative planning estimates. It was demonstrated that the 3DP-RP assisted procedure resulted in more effective reduction of the NSA. Furthermore, patients undergoing 3DP-RP experienced a significant reduction in duration of surgery (P<0.01), as well as reductions in intraoperative (P=0.02) and postoperative (P=0.03) blood loss, compared with conventional surgery. At 6 months post-surgery, no cases of hip varus/vague deformities or implant failure were observed in patients that underwent either the 3DP-RP-assisted or conventional procedure. The results of the present study suggest that the 3DP-RP technique is able to create an accurate model of the ITF, which facilitates surgical planning and fracture reduction, thus improving the efficiency of PFNA surgery for ITFs.

Biomechanical effects of semi-constrained integrated artificial discs on zygapophysial joints of implanted lumbar segments.

This study aimed to optimize the design and application of semi-constrained integrated artificial discs (SIADs) using a finite element (FE) analysis following implantation, wherein the zygapophysial joints of the segment were biomechanically reconstructed. An FE model of the L4-L5 segment was constructed. Variations in the stresses on the discs and zygapophysial joints were observed during 5° anteflexion, 5° extension and 5° rotation under the 400-N applied axial load. Stresses and load translation analyses of the discs and zygapophysial joints were conducted during anteflexion, extension and rotation under the 400-N applied axial load. Following implantation of the lumbar segments, the stresses on the SIAD zygapophysial joints were not significantly different from those of physiological discs during anteflexion, and these were both marginally greater compared with those of non-constrained artificial discs (NADs). During extension, the increase in the stress on the SIAD zygapophysial joints was less than that on NAD zygapophysial joints. Stresses on the NAD zygapophysial joints were higher than those on SIAD and physiological discs during rotation. The stress on the SIAD zygapophysial joints was not significantly different from that on physiological discs during rotation. For SIADs and NADs, the stresses on the zygapophysial joints and the displacements of the discs were greater compared with those of the physiological discs during extension. The SIADs affected the variations in the stresses on the implanted segment more than the NADs, and the SIADs protected the zygapophysial joints of the implanted segment to a higher degree than the NADs.

[The application of biopsy and kyphoplasty in the diagnosis and treatment of osteoporotic thoracolumbar vertebral compression fracture nonunion].

OBJECTIVES: To investigate the clinical efficacy and safety of biopsy and Kyphoplasty in the diagnosis and treatment of osteoporotic thoracolumbar vertebral fracture nonunion, and to explore the clinical characteristics of the disease. METHODS: From July 2005 to May 2010, the clinical data of 8 patients with nonunion of osteoporotic thoracolumbar vertebral fractures were studied. There were 3 males and 5 females, with the mean age of 73.5 years (range, 65 - 86 years). The fracture vertebrae were 3 cases in T(12), 4 in L(1), and 1 in L(2). All cases received radiography, CT and MRI examination. All patients were treated by using Kyphoplasty. Five patients were performed bone biopsy successfully, 3 patients were failed. The curative effect was evaluated by visual analogue scale (VAS), anterior vertebral height restoration at preoperative, postoperative and followed-up time. RESULTS: All patients tolerated the procedure well with immediate relief of back pain after Kyphoplasty. No severe complications were found in all patients. Three cases had the pathologic appearance of sequestrum, 2 cases were sparse cancellous bone, 3 cases were abortive to biopsy. All the patients were followed up of 22.6 months (range, 3 - 37 months), the VAS was 9.5 before operation, 2.1 at the third day postoperatively, there were significant difference between the two phase (P < 0.05), and 2.3 at last follow-up, there were no difference between postoperation and follow-up phase (P > 0.05). And the height of compressed body recovered markedly. The vertebral height had a recovery rate of 67.2% postoperatively, 64.1% and at last follow-up, there were no difference between the two phase (P > 0.05). CONCLUSIONS: Kyphoplasty is an effective and safe method in the treatment of osteoporotic throacolumbar vertebral fracture nonunion. Bone biopsy can play a further role of differential diagnosis.

Effects of a new shape-memory alloy interspinous process device on pressure distribution of the intervertebral disc and zygapophyseal joints in vitro.

OBJECTIVE: To quantify the pressure distribution of lumbar intervertebral discs and zygapophyseal joints with different degrees of distraction of the interspinous processes by using a new shape-memory interspinous process stabilization device, and to research the relationship between changing disc and zygapophyseal joint loads and the degree of distraction of interspinous processes, and thus optimize usage of the implant. METHODS: Six cadaver lumbar specimens (L(2)-L(5)) were loaded. The loads in disc and zygapophyseal joints were recorded at each L(3-4) disc level. Implants with different spacer heights were then placed by turn and the pressure measurements repeated. RESULTS: An implant with 10 mm spacer height does not significantly share the load. A 12 mm implant reduces the posterior annulus load, and meanwhile decreases the zygapophyseal joints pressure, but only in extension. A 14 mm implant shares the loads of posterior annulus, nucleus, and zygapophyseal joints in extension and the neutral position, but slightly increases the anterior annulus' load. Though 16-20 mm implants do decrease the loads in the posterior annulus and zygapophyseal joints, the anterior annulus' load was apparently increased. CONCLUSION: Different degrees of distraction of the interspinous processes lead to different load distribution on the intervertebral disc. The implant tested is not appropriate in cases of serious spinal stenosis because of the contradiction that, while over-distraction of the interspinous processes decreases the posterior annulus and the zygapophyseal joints load and distracts the intervertebral foramina, it leads to a marked increase in the load of the anterior annulus, which is recognized to accelerate disc degeneration.

[Keyhole partial laminectomy and tapping technique combined blind transpedicular screw placement in cervical spine].

OBJECTIVE: To investigate the clinical efficacy and safety of keyhole partial laminectomy and tapping technique combined blindly transpedicular screw placement in cervical spine. METHODS: Keyhole partial laminectomy and tapping technique combined blindly transpedicular screw placement, was introduced. It was performed in 40 patients. The fusion and screw position were observed in postoperative X-ray and CT, and the breach of pedicle were evaluated. Neurological improvement was followed up. RESULTS: Thirty-one cases were followed up, the mean follow-up period was 35 months. 28 cases screw fixation firmly and fusion completely, 3 cases fusion partly and no screw loosening. only 6.74% had a critical breach. Neurological function were improved in 29 cases of spinal cord injuries, only critical complication in one case. CONCLUSIONS: Keyhole partial laminectomy and tapping technique. combined blind placement is one of most usefull, feasible and safe procedures in transpedicular screw placement of the cervical spine.