Posterior osteosynthesis with monoaxial lateral mass screw-rod system for unstable C1 burst fractures.

BACKGROUND CONTEXT: Surgical treatment for unstable atlas fractures has evolved in recent decades from C1-C2 or C0-C2 fusion to motion-preservation techniques of open reduction and internal fixation (ORIF). However, regardless of a transoral or a posterior approach, the reduction is still not satisfactory. PURPOSE: The article describes and evaluates a new technique for treating unstable atlas fractures by using a monoaxial screw-rod system. STUDY DESIGN: This is a retrospective study. PATIENT SAMPLE: The sample includes adult patients with unstable C1 fractures treated with a posterior monoaxial screw-rod system. OUTCOME MEASURES: The outcome measures included a visual analog pain scale, radiographic reduction (lateral mass displacement [LMD]), maintenance of reduction, C1-C2 instability (anterior atlantodens interval), and complications. MATERIALS AND METHODS: From August 2013 to May 2016, nine consecutive patients with unstable atlas fractures were retrospectively reviewed. All patients were treated with posterior ORIF by using a monoaxial screw-rod system. The medical records and the preoperative and postoperative radiographs were reviewed. Preoperative and postoperative computed tomography scans were used to specify the fracture types and to assess the reduction. RESULTS: All nine patients with a mean age of 50.3 years successfully underwent surgery with this technique, and a follow-up of 17.4±9.3 months was performed. Transverse atlantal ligament (TAL) injury was found in eight of the nine patients: one of type I and seven of type II. The preoperative LMD averaged 7.0±2.2 mm and was restored completely after surgery; all the fractures achieved bony healing without loss of reduction or implant failure. None of the patients had complications of neurologic deficit, vertebral artery injury, or wound infection associated with the surgical procedure. Two patients complained of greater occipital nerve neuralgia after the operation, which gradually disappeared in 1 month. All patients had a well-preserved range of motion of the upper cervical spine at the final follow-up. CONCLUSIONS: Posterior osteosynthesis with a monoaxial screw-rod system is capable of an almost anatomical reduction for the unstable atlas fractures. The TAL incompetence may not be a contraindication to ORIF for C1 fractures, but the long-term effect of C1-C2 instability remains to be further investigated.

Relative potency ratio between hyperbaric and isobaric solutions of ropivacaine in subarachnoid block for knee arthroscopy.

OBJECTIVE: To observe the potency ratio of hyperbaric to isobaric solutions of ropivacaine in subarachnoid block for knee arthroscopy. METHODS: Fifty patients receiving knee arthroscopy under combined spinal-epidural anesthesia were randomly divided into isobaric ropivacaine group and hyperbaric ropivacaine group (0.5% ropivacaine, prepared with equal volume of 10% glucose and 1% isobaric ropivacaine). Successful criteria of spinal anesthesia were (1) a bilateral loss of pinprick sensation at or above the level of T12; (2) adequate motor block during knee arthroscopy (modified Bromage's score ≥2); and (3) no requirement of additional epidural administration at least within 60 min after intrathecal injection. Drug consumption was determined with up-and-down method, and then ED50 was calculated. RESULTS: The ED50 of isobaric ropivacaine was 9.71 mg (95% CI 8.11-11.32), and the ED50 of hyperbaric ropivacaine was 6.55 mg (95% CI 6.07-7.04), and the relative potency ratio was 0.67 (95% CI 0.56-0.80) for hyperbaric/isobaric ropivacaine. CONCLUSIONS: The ED50 of hyperbaric ropivacaine is less than that of isobaric ropivacaine in subarachnoid block anesthesia for knee arthroscopy.

Surgical management of the fractures of axis body: indications and surgical strategy.

PURPOSE: The axis body fractures are relatively uncommon and have a variety of presentations. Surgical management to them has been only reported as case reports or included as a minor part of clinical management. The objective of this study is to summarize the indications for surgery and report the clinical outcome of surgical treatment based on different fracture patterns. METHODS: A retrospective analysis of 28 consecutive patients presenting with the axis body fractures was undertaken. The indications for surgical treatment were defined as: (1) fractures associated with instability of adjacent joints; (2) irreducible displaced superior articular facet fracture; (3) fractures resulting in spinal cord compression. The fractures were classified as sagittal, coronal, transverse and lateral mass fracture. One of the following surgical procedures was applied according to the fracture pattern: posterior C1-C2 pedicle screws fixation and fusion (I); posterior C1-C3 screws fixation and fusion (II); posterior osteosynthesis with C2 transpedicular half-thread lag screws (III). RESULTS: 13 patients were successfully managed operatively. Two transverse and two unilateral lateral mass fractures were treated with surgical procedure I, five sagittal fractures with II, four coronal fractures with III. Complications of malposition of screws and neurologic deficit did not occur during operation. Satisfactory reduction and bony union were demonstrated on postoperative radiographics. CONCLUSIONS: Conservative treatment is still advocated as primary management for most axis body fractures. But for patients with obvious adjacent joints instability or irreducible displaced superior articular facet fracture, surgical intervention based on the different fracture pattern is necessary.

[Effects of tourniquet on cardiac function in total knee arthroplasty with trans-esophageal echocardiography].

OBJECTIVE: To employ trans-esophageal echocardiography (TEE) to observe the tourniquet's influence on cardiac function in total knee arthroplasty (TKA). METHODS: Twenty ASA I-II patients undergoing TKA under general anesthesia from September 2011 to February 2012 at Department of Orthopedics, Beijing Jishuitan Hospital were selected. Tourniquet was loosened at 30 minutes after the start of TKA. And TEE was employed to observe the occurrence rate and degree of intra-cardiac embolus and the changes of cardiac function at 5, 10 and 15 min post-loosening respectively. RESULTS: Different degrees of "meteor-shaped" microemboli images appeared in right atriums of all patients. The "meteor shape" image was the most obvious after loosening for 5 min. It started to decrease after 10 min, persisted generally and declined further after 15 min. The left ventricular areas at end diastole (LVAd) after loosening tourniquet for 5, 10 and 15 min were (7.62 ± 0.54), (7.86 ± 0.46) and (8.55 ± 0.56) cm(2) respectively. And there were remarkable changes compared with the area (9.80 ± 0.48) cm(2) pre-loosening (P < 0.01). The fractional area change (FAC) showed obvious decrease since loosening for 5 min (P < 0.01). CONCLUSION: Massive meteor-shaped microembolis appear on TEE with weakened cardiac function.

[The application of C1-2 pedicle screw fixation in treating atlantoaxial instability].

OBJECTIVE: To explore the feasibility of C1-2 pedicle screw fixation and fusion technique in treating atlantoaxial instability. METHODS: From January 2006 to January 2009,18 patients with atlantoaxial instability were treated with C1-2 pedicle screws and plates fixation under general anesthesia. There were 11 males and 7 females, the age for 17-62 years with the mean of 37.7 years. The course of disease was from 3 days to 30 months with an average of 10.6 months. The patients had different degrees neck pain and disturbance of sensation or (and) dyskinesia, had atlantoaxial instability from images before operation. The JOA scoring before operation were from 8 to 15 with an average of 11.4. Bone fusion of patients was observed with X-rays, CT and MR image at the same time after operation and the JOA scoring was compared with preoperative. RESULTS: A total of 72 screws were successfully placed in 18 cases, among them, 15 cases were followed up from 6 to 24 months with an average of 11.5 months. Fifteen cases obtained bone fusion with time for 3-6 months without the complications of internal fixation failure or redislocation of atlas. The spinal compression had differently improved, postoperative JOA scoring was from 12 to 17 scores with an average of 14.5 scores. CONCLUSION: Pedicle screw fixation and fusion in atlas has advantages of firm fixation and high fusion rate, it is a better choices for atlantoaxial instability. It is not suitable for variations of sulcus of vertebral artery of atlas and posterior arch of atlas.

[Changes of IFN-gamma, IL-2, IL-6 and IL-10 in the patient with cardiac surgery under combined acupuncture anesthesia].

OBJECTIVE: To observe the effect of electroacupuncture (EA) on cytokines in the cardiac surgical patient and to evaluate the application of combined acupuncture anesthesia to cardiac surgery. METHODS: Thirty patients with atrial septal defect were divided into 3 groups, general anesthesia group (A), acupuncture anesthesia group (B) and combined general anesthesia and EA group (C). Peripheral blood samples were collected before anesthesia, before cardiopulmonary bypass (CPB), 30 min after CPB and 24 h after operation to determine the levels of interferon-gamma (IFN-gamma), interleukin-2 (IL-2), IL-6 and IL-10. RESULTS: The levels of IFN-gamma and IL-2 decreased in the 3 groups after CPB and further decreased 24 h after operation, and in the group C were higher than those in the group B. The levels of IL-6 and IL-10 significantly increased 24 h after operation in the 3 groups with no significant difference among the 3 groups. CONCLUSION: The general anesthesia combined with EA can not completely improve the decrease of IFN-gamma and IL-2 induced by CPB, indicating that the good response of the general anesthesia combined with EA to stress can partially improve the immunosupression induced by CPB. Acupuncture does not have significant effect on inflammatory cytokine reaction induced by cardiac surgery.

[The study of the C5 nerve root palsy after surgery of cervical spondylosis].

OBJECTIVE: To explore the clinical features, treatment and prognosis of the C5 palsy after surgery of cervical spondylosis. METHODS: Two hundred and twenty-three cases treated from March 1994 to October 2003 were retrospectively reviewed. RESULTS: Seven of the 223 cases developed the complication of C5 palsy, manifesting the paresis of the deltoid muscle as well as the sensory deficits and (or) intractable pain in shoulder. The incidence was 3.1%. In this study, 2 cases occurred in the anterior subcorpectomy, 5 cases developed in the laminoplasty with 1 case on the opened side, 3 cases on the hinged side and 1 case on both sides. All the 7 cases with the C5 palsy recovered within 2 weeks to 6 months. CONCLUSION: The C5 palsy can develop either anterior decompression or posterior open-door laminoplasty of cervical spondylosis. Generally speaking, patients with postoperative C5 palsy can be cured by conservative measures. And prognosis is good.

[Effect of acupuncture-drug compound anesthesia on alteration of immune function in patients undergoing open-heart surgery].

OBJECTIVE: To observe the effect of electro-acupuncture (EA) on alteration of immune function of patients undergoing open-heart surgery with cardiopulmonary bypass (CPB), and to appraise the value of acupuncture-drug compound anesthesia in the operation. METHODS: Thirty patients undergoing atrial septal defect repairing operation were selected and divided into three groups, Group A was the general anesthesia group; Group B, the acupuncture anesthesia group and Group C, the general anesthesia plus EA group. Peripheral venous blood of patients was collected at different time points, i.e. before anesthesia, before CPB, 30 min and 24 hrs after CPB, to determine natural killer cells activity (NKCA), and the levels of interferon-gamma (IFN-gamma) and interleukin-2 (IL-2) in supernatant of cell culture were also tested. RESULTS: NKCA was significantly lowered in Group A before CPB but increased in Group B, while no evident change was found in Group C, so the level of NKCA in Group B was significantly higher than in the other two groups. It lowered in all the three groups after CPB, especially evidently in Group B, so as to cause the NKCA level in Group B lower than that in Group A. The lowering further progressed, 24 hrs after CPB, NKCA in Group B was more reduced than that in Group C. Levels of IFN-gamma and IL-2 lowered in all the three groups after CPB, and further lowered at time point of 24 hrs after CPB, but the parameters in Group C were significantly higher than those in Group B. CONCLUSION: EA could enhance NKCA, but acupuncture anesthesia couldn't inhibit the suppressive effect of CPB on NKCA, IL-2 and IFN-gamma, suggesting that the immunosuppression induced by stress has a prior effect. General anesthesia plus EA yielded better effect than general anesthesia and acupuncture anesthesia, but it could't improve the immunosuppression completely, indicating that the compound anesthesia could partially improve the immunosuppression induced by CPB.