OBJECTIVE: To evaluate the prevalence of deltoid ligament and distal tibiofibular syndesmosis injury on 3T magnetic resonance imaging (MRI) in patients with chronic lateral ankle instability (CLAI). MATERIALS AND METHODS: Fifty patients (mean age, 35 years) who had undergone preoperative 3T MRI and surgical treatment for CLAI were enrolled. The prevalence of deltoid ligament and syndesmosis injury were assessed. The complexity of lateral collateral ligament complex (LCLC) injury was correlated with prevalence of deltoid or syndesmosis injuries. The diagnostic accuracy of ankle ligament imaging at 3T MRI was analyzed using arthroscopy as a reference standard. RESULTS: On MRI, deltoid ligament injury was identified in 18 (36%) patients as follows: superficial ligament alone, 9 (50%); deep ligament alone 2 (11%); and both ligaments 7 (39%). Syndesmosis abnormality was found in 21 (42%) patients as follows: anterior inferior tibiofibular ligament (AITFL) alone, 19 (90%); and AITFL and interosseous ligament, 2 (10%). There was no correlation between LCLC injury complexity and the prevalence of an accompanying deltoid or syndesmosis injury on both MRI and arthroscopic findings. MRI sensitivity and specificity for detection of deltoid ligament injury were 84% and 93.5%, and those for detection of syndesmosis injury were 91% and 100%, respectively. CONCLUSION: Deltoid ligament or syndesmosis injuries were common in patients undergoing surgery for CLAI, regardless of the LCLC injury complexity. 3T MRI is helpful for the detection of all types of ankle ligament injury. Therefore, careful interpretation of pre-operative MRI is essential.
Adolescent ; Adult ; Ankle Injuries/pathology/*radiography ; Ankle Joint/*radiography ; Arthroscopy ; Chronic Disease ; Female ; Humans ; Joint Instability/pathology/radiography/*surgery ; Ligaments, Articular/pathology/radiography ; *Magnetic Resonance Imaging ; Male ; Middle Aged ; Young Adult

OBJECTIVETo study the role of lateral collateral ligament complex on the posterolateral rotatory instability and the relationship between the radiocapitellar ratio (RCR) and the injury of lateral collateral ligament complex on X-ray images.

METHODSTwenty elbow joints from fresh-frozen adult cadavers were used to make osteo-ligamentous elbow specimens. The specimens were fixed with a self-made device to maintain posterolateral rotatory instability of the elbow joint. All the specimens were divided into two groups: group A and group B. Surgical procedures were carried out as follows in the lateral structures of group A: A1, intact specimen; A2, transection of radial ulnar collateral ligament firstly; A3, transection of annular ligament secondly; A4, final transection of the radial collateral ligament. The procedures in group B were carried out as follows: B1, intact specimen; B2, transection of the radial collateral ligament firstly; B3, transection of the annular ligament secondly; B4, final transection of the radial ulnar collateral ligament. Lateral X-ray films of elbow joint were taken, and the radiocapitellar ratio (RCR) was measured by using PACS. All analysis was performed with SPSS 17.0 software.

RESULTSGroup A: the increases in RCR had statistical differences among A1, A2, A3, and A4 groups. Group B: the increases in RCR had no statistical differences among B1, B2 and B3 groups; but the increase in RCR in group B4 was more than that in B1, B2 and B3 groups.

CONCLUSIONThe radial ulnar collateral ligament is a key structure to maintain posterolateral rotatory stability;the radial collateral ligament and the annular ligament are the secondary important structures. There are 4 grades of the posterolateral rotatory instability of the elbow, according to the X-ray imaging classification.

Collateral Ligaments ; injuries ; Elbow Joint ; diagnostic imaging ; physiopathology ; Female ; Humans ; Joint Instability ; diagnostic imaging ; etiology ; physiopathology ; surgery ; Magnetic Resonance Imaging ; Male ; Radiography

OBJECTIVETo evaluate the therapeutic effects of fixation and fusion with lateral mass screws of the atlas and vertebra dentata pedicle screws for the treatment of upper vertebral instability.

METHODSTen patients with atlantoaxial instability, including 3 with old odontoid fracture and 7 with fresh odontoid fracture (Aderson II) received surgeries for fixation and fusion with lateral mass screws of the atlas and vertebra dentata pedicle screws.

RESULTSNo spinal cord or vertebral artery injuries occurred in these patients after the surgery. The follow-up duration ranged from 3 to 15 months with an average of 8 months. The postoperative JOA scores were from l3.2 to l6.8, with an average of l4.8. Clinical improvement was achieved in 87.5% of the patients, and the implanted bones all fused successfully without internal fixation rupture or mobilization.

CONCLUSIONLateral mass screws of the atlas combined with vertebra dentata pedicle screws allows three-dimensional fixation for treatment of atlantoaxial instability.

Adult ; Atlanto-Axial Joint ; diagnostic imaging ; surgery ; Axis, Cervical Vertebra ; injuries ; surgery ; Bone Screws ; Cervical Atlas ; injuries ; surgery ; Female ; Fracture Fixation, Internal ; methods ; Humans ; Joint Instability ; etiology ; surgery ; Male ; Middle Aged ; Radiography ; Spinal Fractures ; complications ; diagnostic imaging ; surgery ; Spinal Fusion ; methods

OBJECTIVESTo investigate the mechanical properties of bilateral atlantoaxial trans-articular screws and atlas laminar hooks instrumentation with finite element method.

METHODSThere was a volunteer with age of 28 years old, body height 172 cm, body weight of 60 kg and without cervical deformity by X rays. The ligamentous, nonlinear, three-dimensional finite element models of normal upper cervical spine (C0-3) was developed and validated. The destabilized model with bilateral atlantoaxial trans-articular screws and atlas laminar hooks was evaluated for quasistatic loading.

RESULTSThe finite element model of upper cervical spine consists of 229,047 nodes and 152,475 elements, and correlated well with experimental data for all load cases and could be used for experiment. The finite model with bilateral atlantoaxial trans-articular screws and atlas-laminar hooks predicted that the maximum Von Mises Stress was in the region in which screws penetrated the atlantoaxial articular facet. The novel instrumentation resulted in sufficient stability.

CONCLUSIONThe bilateral atlantoaxial trans-articular screws and atlas laminar hooks instrumentation is useful and effective for atlantoaxial arthrodesis.

Atlanto-Axial Joint ; surgery ; Biomechanical Phenomena ; Bone Screws ; Cervical Vertebrae ; diagnostic imaging ; Finite Element Analysis ; Humans ; Imaging, Three-Dimensional ; Internal Fixators ; Joint Instability ; surgery ; Male ; Radiography ; Spinal Fusion ; instrumentation ; methods

OBJECTIVETo evaluate the technique of C1-C2 transarticular screw fixation for atlantoaxial instability or dislocation.

METHODSAmong 14 patients with atlantoaxial instability, 10 were male and 4 patients were female, with an average age of 38.6 years ranging from 17 to 62 years. All patients were treated by internal fixation with transarticular screws.

RESULTSThere were 28 screws applied in 14 patients. All patients were followed up. The average follow-up period was 16 months (range, 9 to 35 months). The postoperative JOA score was ranging from 13.8 to 15.8 with the average score of (14.50 +/- 0.66) and the improved rate of (76.12 +/- 4.94)%. No spinal injury and vertical artery injury was found and osseous fusion was completed in all patients.

CONCLUSIONThe technique of C1-C2 transarticular screw fixation is one of the best treatments for atlantoaxial instability. Without the help of structural bone graft and aided internal fixation, morselized cancellous bone graft can acquire effective osseous fusion.

Adolescent ; Adult ; Atlanto-Axial Joint ; pathology ; surgery ; Bone Screws ; Female ; Follow-Up Studies ; Humans ; Internal Fixators ; Joint Instability ; diagnostic imaging ; physiopathology ; surgery ; therapy ; Male ; Middle Aged ; Radiography ; Tomography Scanners, X-Ray Computed ; Treatment Outcome ; Young Adult

OBJECTIVETo study the examination,surgical opportunity and surgery methods of lost instability of traumatic dislocation of the knee joint.

METHODSSixty-three patients (48 males and 15 females,ranging in age from 16 to 75 years,with an average of 36.6 years) were checked, treated and followed up from January 2001 to April 2006. According to classification of Wascher for knee dislocation, there was 1 case of KD-I, 13 KD-II, 17 KD-III, 18 KD-IV, 14 KD-V. Stability of the knee was evaluated by physical and radiological examinations, of which 53 patients were treated with open surgery, 4 patients were treated with arthroscope, 4 patients were treated with arthroscope and open surgery, 1 patient was treated with amputation, 1 patient was treated with total knee arthroplasty.

RESULTSThe detection rate of MRI was 100% (39/39), stress radiography was 100% (19/19), arthroscpoe was 93.3% (14/15). According to Lysholm Criteria for knee joint function,the preoperative Lysholm score in old traumatic group was 37.17 +/- 5.33, fresh traumatic group was 37.41 +/- 5.38. The postoperative Lysholm score in old traumatic group was 67.33 +/- 14.72, fresh traumatic group was 82.45 +/- 12.13 (Z = -3.061, P = 0.002).

CONCLUSIONMRI stress radiography and arthroscope do well for the evaluation of stability of the knee. Instable traumatic dislocation of the knee joint must be operated promptly. Fresh instable dislocations of knee prefer repair,old instable dislocations of knee prefer reconstruction.

Adolescent ; Adult ; Aged ; Arthroscopy ; Female ; Humans ; Joint Instability ; diagnosis ; rehabilitation ; surgery ; therapy ; Knee Dislocation ; diagnosis ; rehabilitation ; surgery ; therapy ; Knee Joint ; diagnostic imaging ; physiopathology ; surgery ; Male ; Middle Aged ; Physical Examination ; Radiography

OBJECTIVETo evaluate the operative strategy and therapeutic outcomes of the atlantoaxial instability.

METHODSClinical data of 29 patients with atlantoaxial instability were retrospectively analyzed. There were 27 males and 2 females. The mean age was 33 years old with a range from 18 to 54 years. There were fracture of anterior arch of atlas accompanied with ligamentum transversum rupture in 5 cases, odontiod fracture in 7 cases, Hangman fracture in 6 cases, dysplasia of atlas and axis in 10 cases, ankylosing spondylitis in 1 case. The clinical and imaging manifestation of atlantoaxial instability were found in all patients. The symptoms and physical signs of superior cervical spinal cord disease or cervical spinal injury were found in 18 cases. The patients were treated with simple modified Magerl method (7 cases), cannutated screw fixation(6 cases), resection of C2,3 disc throuth the anterior approach and fusion with Zephir titanium plate (4 cases), percutaneous pedicle screw fixation of C2 (2 cases), release and reduction through anterior oropharynx (LRAO) combined with modified Magerl method (4 cases), LRAO and atlas lateral mass screw and plate fixation through posterior approach (3 cases), cervical occipital fusion through C2 pedicle (3 cases).

RESULTSAll patients were followed up with an average time of 17.2 months ranging from 11 to 38 months. All patients obtained anatomical reduction and bone healing. Using Odom standard to evaluation for 18 cases with spinal injury before operation, the results were excellent in 9 cases,good in 7,fair in 2. No injury of vertebral artery, nerve root, spinal cord, infection of incisional wound, breaking or loosening of internal fixatir were found in the study.

CONCLUSIONIdentifying the causes of atlantoaxial instability, rational plan of operation can get satisfactory clinical results.

Adolescent ; Adult ; Atlanto-Axial Joint ; diagnostic imaging ; surgery ; Female ; Humans ; Joint Instability ; diagnostic imaging ; surgery ; Male ; Middle Aged ; Radiography ; Retrospective Studies

This study aims to assess the effectiveness and advantages of Vertex multiaxial screw system in use for stabilizing the atlanto-axial junction. The entry point of the atlas was located 18-20 mm lateral to the midline and 2.0 mm superior to the inferior border of posterior arch, and the direction of screw was chosen to be about 10 degrees medial to the sagittal plane and about 5 degrees cephalad to the transverse plane. In odontoid vertebra (C2), the direction of the drill bit was guided directly by the medial and superior aspect of the individual C2 pedicle. All screws were placed properly without incidence of nerve or blood vessel injury, and no complication appeared in operation and after surgery. All cases were followed up for an average of 9 months, all cases achieved well reposition and fixation of atlantoaxial joint, average JOA grade was 9.6 before preoperation and 15.9 after operation. Fixation of the atlantoaxial complex using Vertex multiaxial screw system seemed to be a reliable technique and should be considered a good alternative in atlantoaxial fusion. The technique could be used in young patiens.
Adolescent ; Adult ; Atlanto-Axial Joint ; diagnostic imaging ; surgery ; Bone Screws ; Child ; Female ; Follow-Up Studies ; Humans ; Joint Instability ; surgery ; Male ; Middle Aged ; Radiography ; Spinal Fusion ; instrumentation

The mechanics of a new shape memory alloy cervical hook for atlantoaxial instability was analyzed with finite element method on the basis of a three-dimensional model reconstructed from the images of CT scanning of an adult cadaveric upper cervical at 1-mm interval. The stress and displacement of every nodule and element in the course of deformation of the internal fixation were tested, and the results showed that the cervical hook was strong enough against tensile stress, which concentrates in the middle of the device. The pull was 237.58 N at the loading point. With such mechanical performance, this cervical hook can be reliable for correction of atlantoaxial instability.
Adult ; Alloys ; Atlanto-Axial Joint ; Cadaver ; Finite Element Analysis ; Humans ; Joint Instability ; diagnostic imaging ; surgery ; Male ; Memory ; Orthopedic Fixation Devices ; standards ; Orthopedic Procedures ; instrumentation ; methods ; Radiography ; Reproducibility of Results ; Tensile Strength

This study sought to determine the outcomes of posterior lumbar interbody fusion (PLIF), via a unilateral approach, in selected patients who presented with unilateral leg pain and segmental instability of the lumbar spine. Patients with a single level of a herniated disc disease in the lumbar spine, unilateral leg pain, chronic disabling lower back pain (LBP), and a failed conservative treatment, were considered for the procedure. A total of 41 patients underwent a single-level PLIF using two PEEK(TM) (Poly-Ether-Ether-Ketone) cages filled with iliac bone, via a unilateral approach. The patients comprised 21 women and 20 men with a mean age of 41 years (range: 22 to 63 years). Two cages were inserted using a unilateral medial facetectomy and a partial hemilaminectomy. At follow-up, the outcomes were assessed using the Prolo Scale. The success of the fusion was determined by dynamic lumbar radiography and/or computerized tomography scanning. All the patients safely underwent surgery without severe complications. During a mean follow-up period of 26 months, 1 patient underwent percutaneous pedicle screw fixation due to persistent LBP. A posterior displacement of the cage was found in one patient. At the last follow up, 90% of the patients demonstrated satisfactory results. An osseous fusion was present in 85% of the patients. A PLIF, via a unilateral approach, enables a solid union with satisfactory clinical results. This preserves part of the posterior elements of the lumbar spine in selected patients with single level instability and unilateral leg pain.
Treatment Outcome ; Spinal Fusion/*methods ; Middle Aged ; Male ; Lumbar Vertebrae/radiography/*surgery ; Joint Instability/radiography/*surgery ; Intervertebral Disk Displacement/radiography/*surgery ; Humans ; Follow-Up Studies ; Female ; Adult