踝关节本体感受器损伤与慢性踝关节不稳定关系的初步研究

目的 从新鲜尸体和踝关节不稳患者手术中所切取的韧带周围组织入手,分析踝关节周围本体感受器的性质和分布,并进一步与临床病例的生物力学、本体感觉功能检验结果相比较,判断和分析本体感受器受损在功能性踝关节不稳定中的作用.方法18例踝关节不稳患者行韧带重建手术.术前、术后分别行功能评分[美国骨科足踝医师协会(AOFAS)评分],平衡系统评价其本体感觉功能.从2例新鲜冰冻尸体踝关节韧带组织和手术中获取韧带组织标本,应用组织学方法和免疫组化染色观察分析感觉小体的结构特征和分布特点.结果 (1)标本发现Ⅰ型小体、Ⅱ型小体和Ⅳ型游离无神经鞘的神经末梢;这些感受器主要分布于韧带的浅层和近骨附着部.(2)患者重心摆动距离术前、术后睁眼与闭眼检测差异均有统计学意义;患者AOFAS评分手术前后差异有统计学意义.结论(1)踝关节不稳患者本体感觉功能受损,病史越长,症状越严重,功能评分越低,其本体感受受损越严重.(2)韧带感受器受损,与踝关节不稳症状相关联,韧带重建是避免感受器反复损伤的有效方法.

Abstract：

Objective To analyze the effect of ankle joint proprioceptor injury on the functional ankle instability. Methods The study enrolled 18 ( 13 males) with chronic ankle instability treated with ligament reconstruction operation. The American Orthopaedic Foot and Ankle Surgeons (AOFAS)score was used for evaluation of the function before and after operation and the balance system evaluate the proprioception function. The two ankle ligament specimens from fresh frozen body and the tissue samples from operation were used for investigation of the structure and distribution of the sensory corpuscles by using histology and immunohistoehemical staining. Results The sections were evaluated with a microscope and an image analyzer. Labeled nerve endings were mapped, measured and categorized. Type Ⅰ ( Ruffini-like ending) , type Ⅱ ( Pacinin-like corpuscle ) and type Ⅳ- (noncorpuscular) nerve endings could be identified in all the lateral ankle ligaments, with majority of types Ⅰ and Ⅱ nerve endings.These receptors were distributed primarily over the superficial ligament and near the bony attachments.There was statistical difference between preoperative and postoperative sway distance as well as between preoperative and postoperative AOFAS score. Conclusions This study suggests that the longer history,severer symptoms and lower AOFAS score may lead to the severer injury of the mechanical proprioceptors.The proprioceptor injury is correlated with ankle joint instability and the ligament reconstruction is effective to avoid the repeated injury of the proprioceptor.     

寰枢椎后路三种组合固定技术治疗寰枢关节不稳的临床评估

Objective To assess clinical curative effect of three types of combined posterior atlantoaxial internal fixation techniques in treatment of atlantoaxial instability. Methods The study involved 68 patients with atlantoaxial instability treated with different fixation techniques from August 2002 to March 2008. ( 1 ) Transpedicular fixation was performed in 32 patients including 20 patients with Anderson Ⅱ odontoid fractures (seven with old odontoid fracture and 13 with fresh fractures), six with type Anderson Ⅲ fresh odontoid fractures, four with disrupt of transverse ligament of the atlas and two with congenital loose odontoid process combined with atlantoaxial instability. (2) Transpedicular internal fixation with screws of atlas incorporating C2 laminar screws was performed in 20 patients with upper cervical injury including eight with type Ⅱ odontoid process fractures combined with atlantoaxial backward dislocation,four with type Ⅱ odontoid process fractures combined with atlantoaxial forward dislocation, two with nonunion of odontoid process fractures, three with type Ⅲ odontoid process fractures combined with atlantoaxial unsteadiness and three with atlantoaxial dislocation combined with disrupt of transverse ligament of atlas. (3)A total of 16 patients with traumatic atlantoaxial instability, reducible atlantoaxial dislocation and irreducible atlantoaxial dislocation were treated with four-point internal fixation technique using autologous iliac bone grafts. Results (1) A total of 120 screws were implanted in 32 patients, with no spinal cord or vertebral artery injury after surgery. Atlas lateral mass fixation was adopted in three patients because of broken posterior arch of the atlas. Postoperative CT showed that two screws were inserted into the vertebral artery hole and that one screw was inserted medially into the spinal canal and caused medial correx rupture, but both with no clinical symptoms. All 32 patients were followed up for 6-42 months ( average 26 months), which showed solid fusion in all patients. The postoperative JOA scores ranged from 13.2 points to 16.8 points (average 14. 8 points). (2) Thirty-two screws were implanted in 20 patients,with no spinal cord or vertebral artery injury. The patients were followed up for mean six months ( range 6-14 months). Postoperative X-ray showed sound bone fusion, with no cervical instability, loosening or breakage of the screws. (3) The symptoms of all the patients were improved at different degrees, with no neurological deterioration or severe complications, such as nerve blood vessel injury. All 16 patients were followed up for 8-26 months ( average 16 months), which showed bony fusion in all patients at 3-6 months after surgery. The spinal cord function was improved markedly in five patients, good in eight, mild in two but unchanged in one. Conclusions Three types of combined posterior atlantoaxial internal fixation techniques have advantages of rigid, short-segmental and three-dimensional fixation and hence are effective methods for treatment of upper cervical injuries. The combination mode can be varied according to specific condition of the patients.     

寰枢椎后路三种组合固定技术治疗寰枢关节不稳的临床评估

Objective To assess clinical curative effect of three types of combined posterior atlantoaxial internal fixation techniques in treatment of atlantoaxial instability. Methods The study involved 68 patients with atlantoaxial instability treated with different fixation techniques from August 2002 to March 2008. ( 1 ) Transpedicular fixation was performed in 32 patients including 20 patients with Anderson Ⅱ odontoid fractures (seven with old odontoid fracture and 13 with fresh fractures), six with type Anderson Ⅲ fresh odontoid fractures, four with disrupt of transverse ligament of the atlas and two with congenital loose odontoid process combined with atlantoaxial instability. (2) Transpedicular internal fixation with screws of atlas incorporating C2 laminar screws was performed in 20 patients with upper cervical injury including eight with type Ⅱ odontoid process fractures combined with atlantoaxial backward dislocation,four with type Ⅱ odontoid process fractures combined with atlantoaxial forward dislocation, two with nonunion of odontoid process fractures, three with type Ⅲ odontoid process fractures combined with atlantoaxial unsteadiness and three with atlantoaxial dislocation combined with disrupt of transverse ligament of atlas. (3)A total of 16 patients with traumatic atlantoaxial instability, reducible atlantoaxial dislocation and irreducible atlantoaxial dislocation were treated with four-point internal fixation technique using autologous iliac bone grafts. Results (1) A total of 120 screws were implanted in 32 patients, with no spinal cord or vertebral artery injury after surgery. Atlas lateral mass fixation was adopted in three patients because of broken posterior arch of the atlas. Postoperative CT showed that two screws were inserted into the vertebral artery hole and that one screw was inserted medially into the spinal canal and caused medial correx rupture, but both with no clinical symptoms. All 32 patients were followed up for 6-42 months ( average 26 months), which showed solid fusion in all patients. The postoperative JOA scores ranged from 13.2 points to 16.8 points (average 14. 8 points). (2) Thirty-two screws were implanted in 20 patients,with no spinal cord or vertebral artery injury. The patients were followed up for mean six months ( range 6-14 months). Postoperative X-ray showed sound bone fusion, with no cervical instability, loosening or breakage of the screws. (3) The symptoms of all the patients were improved at different degrees, with no neurological deterioration or severe complications, such as nerve blood vessel injury. All 16 patients were followed up for 8-26 months ( average 16 months), which showed bony fusion in all patients at 3-6 months after surgery. The spinal cord function was improved markedly in five patients, good in eight, mild in two but unchanged in one. Conclusions Three types of combined posterior atlantoaxial internal fixation techniques have advantages of rigid, short-segmental and three-dimensional fixation and hence are effective methods for treatment of upper cervical injuries. The combination mode can be varied according to specific condition of the patients.     

巨大肩袖损伤的手术修复结果

Objective To evaluate the clinical results of arthroscopic repair of massive rotator cuff tear. Methods The study involved 16 patients with massive rotator cuff tears treated arthroscopically from September 2007 to June 2009. There were 6 males and 11 females at average age 61.5 years (45-75 years). The rotator cuff tears was repaired with arthroscopic double-row reconstruction. The range of motion, pain, strength of flexed elevation and function evaluation score were all recorded before operation and at final follow-up. The results were evaluated by t test and compared according to age and course of disease. Results All patients were healed without complications and the outcome was improved significantly ( P < 0.01 ). The mean VAS score was improved from preoperative 5.6 to postoperative 1.7,the average forward flexion from 69. 1°to 151.2°, the average external rotation from 14.7° to 32.2°, and internal rotation from L1 level to T10, the mean Constant-Murle from 39 to 85, the mean UCLA from 10.4 to 28, the mean SST from 2.8 to 8.8 and the strength of flexed elevation from 10.7% of normal side to 65.0%. Compared with preoperation, there was statistical difference in aspects of pain, range of motion, muscle strength and function in postoperation (P < 0.01 ). Conclusion Arthroscopic doublerow fixation can attain satisfactory results in repair of massive rotator cuff tear.     

切开复位内固定治疗早期Lisfranc关节损伤

目的 总结分析切开复位内固定治疗早期Lisfranc关节损伤的临床经验.方法 2005-2010年共收治Lisfranc关节损伤12例,男10例,女2例;平均年龄34岁(8-60岁).Myerson分型:A型2例,B型8例,C型2例.所有患者均在伤后17 d内接受手术,手术采用切开复位、螺钉或克氏针内固定.术后采用美国足踝外科协会(American Orthopaedic Foot and Ankle Society,AOFAS)中足评分标准进行功能评估;术前、术后采用X线摄片(正、侧及左右斜位)和CT扫描进行影像学评估.结果 所有患者均获得有效随访,平均随访33个月(6-60个月).术后AOFAS中足评分平均74.5分(53～96分),其中优8例,良2例,中2例.X线片和CT扫描示8例获得解剖复位.所有患者均骨性愈合.本组未见任何手术并发症.结论 切开复位内固定是治疗早期Lisiranc关节损伤的有效方法,术前应结合临床、X线片和CT扫描进行综合分析.

Abstract：

Objective To summarize the clinical experience in treatment of the Lisfranc joint injury with open reduction and internal fixation at early stage. Methods Twelve patients ( including ten males and two females at average age of 34 years) with early stage Lisfranc joint injury received open reduction and screw/wire fixation from 2005 to 2010. According to the Myerson classification, there were two patients with type A, eight with type B and two with type C. All the patients received open reduction and internal fixation with screw or Kirschner wire within 17 days after injury. The post-operative function was estimated by mid-foot scoring scale of AOFAS. X-ray and CT scan were used in radiography estimation. Results All the patients were followed up for average 33 months ( range, 6-60 months). The mean score of post-operative mid-foot scoring scale of AOFAS was 74.5 points ( range, 53-96 points), with excellent result in eight patients, good in two and fair in two. The anatomical reduction was observed in eight patients and all the patients obtained bony union according to the results of X-ray and CT scan.There was no any complication found.Conclusions Open reduction and internal fixation is a good choice for the treatment of Lisfranc joint injury at early stage. A preoperative comprehensive analysis combined with clinical X-ray and CT scan is necessary.     

采用锥形股骨柄生物学固定对高龄患者行全髋置换术后的骨改建及临床疗效

Objective To investigate periprosthetic femoral shaft remodeling with tapered femoral stems after total hip arthroplasty (THA) for elderly patients and evaluate the mid-term clinical outcomes.Methods The study involved 30 elderly (70-90 years) patients (34 hips) treated with femoral shaft remodeling with tapered stems after THA from January 2003 to January 2005. The postoperative X-ray images were collected and perioperative periprosthetic bone mineral density was analyzed by dual-energy X-ray absorptiometry (DEXA). The Harris score was applied in follow-up observation, and Kaplan-Meier method was used to evaluate the working life of the femoral prosthesis. Results Four patients were died of lung cancer. The remaining 26 patients ( 30 hips) were followed up for 5-7 years ( mean, six years). The postoperative X-ray measurements showed that total hip prosthesis subsidences were less than 1.5 mm within one year in 12 hips, with no prosthesis loosening observed. Bone proliferations were seen in Gruen zones 2, 3, 4, 5, 6, 11 and 12, and bone resorptions were seen in zones l and 7. DEXA showed that bone mineral density was increased in Gruen zones 2,3,4 and 5, but decreased mainly in Gruen zones 1,6 and 7. The increase of bone mineral density in zones 2 and 5 was faster compared to other sites six months after the operation ( P ＜ 0.05 ) and the change of bone mineral density was prone to be stable in two years ( P ＞ 0.05 ). Within one year after initial implantation, periprosthetic bone mineral density was significantly decreased ( P ＜ 0.05 ). Two years after the operation, rare changes of periprosthetic bone mineral density were found ( P ＞ 0.05 ), with only regional redistribution of bone mass from the proximal to the distal femur. The Harris score of hip joint function was increased from preoperative 38.56 ± 8.21 to 86.32 ± 6. 01 at the final follow-up. The 6-year survival rate of the prosthesis was 100%. Conclusion Femoral shaft remodeling with tapered stems after total hip arthroplasty for the elderly patients shows good periprosthetic bone remodeling and satisfactory mid-term clinical results.     

Magnetic resonance imaging in glenohumeral instability

The glenohumeral joint is the most commonly dislocated joint of the body and anterior instability is the most common type of shoulder instability.Magnetic resonance (MR) imaging,and more recently,MR arthrography,have become the essential investigation modalities of glenohumeral instability,especially for pre-procedure evaluation before arthroscopic surgery.Injuries associated with glenohumeral instability are variable,and can involve the bones,the labor-ligamentous components,or the rotator cuff.Anterior instability is associated with injuries of the anterior labrum and the anterior band of the inferior glenohumeral ligament,in the form of Bankart lesion and its variants;whereas posterior instability is associated with reverse Bankart and reverse Hill-Sachs lesion.Multidirectional instability often has no labral pathology on imaging but shows specific osseous changes such as increased chondrolabral retroversion.This article reviews the relevant anatomy in brief,the MR imaging technique and the arthrographic technique,and describes the MR findings in each type of instability as well as common imaging pitfalls.     

单纯腹部外伤术后发生急性肾功能衰竭的危险因素分析

Objective To investigate the risk factors associated with acute renal failure (ARF)after surgery in patients with simple abdominal trauma. Methods A retrospective case-control study was carried out in patients with simple abdominal trauma after surgery from January 2003 through May 2008 in our hospital. Twenty patients with ARF were set as study group and 68 patients without ARF as control group. Clinical data including age, gender, injury type, number of injured organs, blood transfusion volume, intra-abdominal pressure, abdominal infection, shock and related factors were analyzed by using univariate and Logistic regression to identify the independent risk factors of ARF after surgery in patients with simple abdominal trauma. Results Univariate analysis revealed statistical difference in aspects of blood transfusion volume ( ＞ 1 600 ml), operation timing ( interval between trauma and operation ＞12 h), preoperative shock duration ( ＞6 h), postoperative abdominal infection and intra-abdominal hypertension ( ＞ 12 mm Hg) between two groups ( P ＜ 0. 05 ). Logistic regression analysis showed that these five indices were the independent risk factors of ARF after surgery in patients with simple abdominal trauma ( P ＜ 0. 05 ). Conclusions Massive blood transfusion, delayed operation, long preoperative duration of shock, postoperative abdominal infection or intra-abdominal hypertension are the risk factors of ARF after surgery in patients with simple abdominal trauma. We should pay attention to these factors and take effective measures to prevent occurrence of ARF.     

术中X线透视定位行LARS韧带重建前交叉韧带的临床价值

目的 探讨在LARS韧带重建前交叉韧带(ACL)手术中,关节镜下运用X线透视定位法的操作特点和临床疗效.方法 2006年6月起运用法国LARS韧带治疗急性膝关节ACL断裂36例,男25例,女11例;年龄22～51岁,平均28.3岁.左膝19例,右膝17例.所有患者术前MRI均提示ACL连续信号中断,膝关节Lysholm评分平均52分.操作在关节镜下完成,其中股骨隧道口定位、胫骨隧道口定位主要依靠术中C形臂X线机定位;LARS韧带直径为7.5 mm,空心挤压螺钉直径为8.0 mm.结果 本组患者获9～20个月(平均18个月)随访.36例患者术前Lysholm评分平均为52分;术后12个月平均为92分.本组优23例,良9例,可4例,近期优良率为89%.结论 在关节镜下运用X线透视定位法进行LARS人工韧带重建膝ACL,操作方便,定位准确,手术效果优良.

Abstract：

Objective To discuss the operation skills and clinical effects of C-arm fluoroscopy in arthroscopic reconstruction of anterior cruciate ligament(ACL)with the Ligament Advancement Reinforcement System(LARS)artificial ligaments.Methods The study involved 36 patients with acute ACL rupture treated with the LARS artificial ligaments from June 2006.There were 25 males and 11 females,at age range of 22-51 years(average 28.3 years),involving 19 left knees and 17 right knees.The results of preoperative MRI of all patients suggested discontinuation of ACL,with average score of Lysholm on knee joint for 50.The operation was completed under arthroscope.While the locations of the femoral tunnel portal and the tibial tunnel exit were mainly determined by the C-arm fluoroscopy.The diameter of the LARS artificial ligament was 7.5 mm while that of the interference screw 8 mm.Results All 36 patients were followed up for a mean duration of 18 months(9-20 months).The average Lysholm Score was 52 preoperatively and 92 at the 12th week after operation.The clinical results were graded as excellent in 23 patients,good in nine and fair in four according to the Lysholm's classification,with excellence rate of 89%.Conclusions Arthroscopic reconstruction of anterior cruciate ligament with LARS artifical ligament under C-arm fluoroscopy takes advantages of convenient operation,accurate location and satisfactory clinical effect.     

骨关节型严重多发伤的救治

Objective To investigate the curative effect of damage control theory in treating severe polytrauma patients combined with bone and joint injury. Methods A retrospective study was done on data including complication, death rate, fracture healing and joint function recovery of 63 patients with severe polytrauma combined with bone and joint injury( average ISS ≥27 points) admitted to our hospital from January 2006 to June 2009. Results Of all the patients, 57 shock patients were cured,three died of hemorrhagic shock within two hours after admission and one patient died of severe traumatic brain injury 11 hours after admission. One patient died of ARDS at 24 hours postoperatively and one died of multiple organ failure at day 6 after injury. Fracture healing was achieved in 52 patients, with satisfactory recovery of the limb function. Amputation was performed in two patients and three patients had mild claudication and pain walking. Conclusion Damage control strategy has great clinical significance in guidance of treatment of severe polytrauma combined with bone and joint injury.     

The placebo effect of ankle taping in ankle instability

PURPOSE: Recurrence of ankle sprains is common among athletes. Although ankle taping reduces the risk of injury, the mechanism underlying its effectiveness remains unclear. Anecdotal reports suggest a role of the belief among athletes that taping will protect them from injury. That is, taping may have a placebo effect. The purpose of the present study was to determine whether there was a placebo effect with ankle taping in individuals with ankle instability. METHODS: Thirty participants with ankle instability completed a hopping test and a modified star excursion balance test under three conditions: (i) real tape, (ii) placebo tape, and (iii) control (no tape). Participants were blinded to the purpose of the study and were informed that the study aimed to compare two methods of ankle taping referred to as mechanical (real) and proprioceptive (placebo). The order of testing the three conditions and the two functional tests was randomized. RESULTS: There was no significant difference in performance among the three conditions for the hopping test (P = 0.865) or the modified star excursion balance test (P = 0.491). However, a secondary exploratory analysis revealed that participants' perceptions of stability, confidence, and reassurance increased with both real and placebo ankle taping when performing the functional tasks. CONCLUSION: The role of the placebo effect of ankle taping in individuals with ankle instability remains unclear. Clinicians should, therefore, continue to use ankle-taping techniques of known efficacy. They should, however, focus on maximizing patients' beliefs in the efficacy of ankle taping, because its application reassured participants and improved their perceived stability and confidence. The effect of ankle taping on participants' perceptions may contribute to its effectiveness in preventing injury.     

人工踝关节置换治疗踝关节病的临床疗效

目的探讨人工踝关节置换治疗踝关节病的疗效。方法对18例患者18踝行人工踝关节置换,其中创伤性踝关节炎9例,骨性踝关节炎6例,创伤后局限性距骨缺血坏死2例,粉碎骨折踝关节融合后1例。结果随访1～5年,按Kofoed评价系统观察疗效,优16例,良2例。患足背伸范围6°～12°,跖屈范围8°～16°,背伸和跖屈11°～23°。并发症有切口皮缘坏死2例,无足内、外翻和影像学松动。结论人工踝关节置换是改善踝关节功能的良好方法。     

Sensorimotor deficits with ankle sprains and chronic ankle instability

The presence of sensorimotor deficits in patients who have suffered ankle sprains or who have chronic ankle instability has been recognized for several decades; however, a body of research literature has developed that elucidates potential physiologic explanations for these deficits. Alterations in a spectrum of sensorimotor measures make it apparent that conscious perception of afferent somatosensory information, reflex responses, and efferent motor control deficits are present with ankle instability. The specific origin of these deficits local to the ankle ligaments or at the spinal or supraspinal levels of motor control have yet to be fully elucidated. It is clear, however, that both feedback and feedforward mechanisms of motor control are altered with ankle instability.     

The effect of osseous ankle configuration on chronic ankle instability

Background

Chronic ankle instability (CAI) is a common orthopaedic entity in sport. Although other risk factors have been studied extensively, little is known about how it is influenced by the osseous joint configuration.

Aim

To study the effect of osseous ankle configuration on CAI.

Design

Case–control study, level III.

Setting

Radiological examination with measurement of lateral x rays by an independent radiologist using a digital DICOM/PACS system.

Patients

A group of 52 patients who had had at least three recurrent sprains was compared with an age‐matched and sex‐matched control group of 52 healthy subjects.

Main outcome measures

The radius of the talar surface, the tibial coverage of the talus (tibiotalar sector) and the height of the talar body were measured.

Results

The talar radius was found to be larger in patients with CAI (21.2 (2.4) mm) than in controls (17.7 (1.9) mm; p<0.001, power >95%). The tibiotalar sector, representing the tibial coverage of the talus, was smaller in patients with CAI (80° (5.1°)) than in controls (88.4° (7.2°); p<0.001, power >95%). No significant difference was observed in the height of the talar body between patients with CAI (28.8 (2.6) mm) and controls (27.5 (4.0) mm; p = 0.055).

Conclusion

CAI is associated with an unstable osseous joint configuration characterised by a larger radius of the talus and a smaller tibiotalar sector. There is evidence that a higher talus might also play some part, particularly in women.Ankle ligament injuries are the most common injuries in sport and recreational activities.¹ The anterior talar‐fibular ligament is affected in 85% of ankle sprains.^2,3,4 This type of injury represents a sprain with a major component in the sagittal plane.^5,6 This kind of injury is therefore best investigated using lateral views of the ankle, where the osseous containment of the talus in the tibia can be assessed. Although most of these ligamentous ankle injuries can be successfully treated with physical rehabilitation and non‐operative treatment, 20–40% of patients with ankle injuries develop chronic ankle instability (CAI) and experience recurrent sprains.^7,8,9,10 Many of these patients with CAI can be satisfactorily treated with reconstruction of the injured ligaments.^{3,11,12,13,14,15,16} However, good results of surgery and physical rehabilitation notwithstanding, some patients keep experiencing persistent symptomatic ankle instability^10,17 and have the propensity to develop post‐traumatic ligamentous ankle osteoarthritis.¹⁸The risk of spraining an ankle depends on both intrinsic factors (hindfoot alignment, ligament laxity, muscular force, neuromuscular control and so on) and extrinsic factors (shoes worn, type and intensity of sport, warm up and so on).^19,20,21 The shoulder, a rather unstable joint, is characterised by a humeral head that is large compared with the glenoid, whereas in the hip, a stable joint, the femoral head and the acetabulum are of equal size. This suggests that there is a relationship between joint stability and osseous joint configuration, but to date, the effect of the osseous configuration on the predisposition to develop CAI has not been investigated.The current study examines whether the osseous joint configuration of the ankle joint plays a role in the development of CAI. The hypotheses of this study were that (a) a flat talus, characterised in terms of a large radius, contributes to CAI; (b) a lack of restraint of the talus in the tibia, characterised in terms of a small tibiotalar coverage, contributes to CAI; and (c) a higher talar body with consequently more torque forces contributes to CAI.     

Ball-and-socket ankle joint

The ball-and-socket ankle joint is a malformation of the ankle in which the articular surface of the talus is hemispherical in both the anteroposterior and lateral projections and has a congruent, concave tibial articular surface. Fourteen patients with this condition were identified retrospectively. Thirteen patients were thought to have the congenital type of ball-and-socket ankle joint which in many was associated with tarsal coalition, short limb, and ray fusion and deletion anomalies. One case of the acquired type, demonstrating less geometric rounding of the talar margins, was seen in a patient with myelomeningocele, probably resulting from sensory and motor deficits. Although the exact etiology of the congenital type is unknown, its association with other malformations suggests that the ball-and-socket ankle joint results from an overall maldevelopment of the ankle and foot.     

The effects of ankle compliance and flexibility on ankle sprains

PURPOSE: The goal of this study was to examine the influence of changes in subtalar joint flexibility and compliance on ankle sprain occurrence. METHODS: Muscle model driven simulations of 10 subjects performing the landing phase of a side-shuffle movement were performed. The passive flexibility or compliance of the subtalar joint was varied, and each subject-specific simulation was exposed to a set of perturbed floor conditions. RESULTS: Increases in flexibility and compliance both led to an increase in the occurrence of excessive supination, while changes in flexibility had a greater influence. Changes in flexibility or compliance caused only small changes in the occurrence of excessive supination torques. CONCLUSION: These results suggest that increased mechanical laxity does not directly cause an increase in sprain occurrence during side-shuffle movements.     

Syndesmotic ankle sprains

In this study we reviewed ankle sprains in a professional football team over a 6 year period. Fifteen players who sustained syndesmotic ankle sprains were compared with 28 players who sustained significant lateral ankle sprains. Players with syndesmotic sprains missed significantly more games and practices and they received substantially more treatments than players with lateral ankle sprains. Physical examination findings, results of radiographic evaluations, and etiologic factors are discussed. The external rotation stress test, a clinical method for diagnosis of this type of sprain at the time of injury, is described. Results of this study clearly demonstrate a prolonged recovery time for syndesmotic ankle sprains. Physicians and trainers who are aware of this injury can differentially diagnose these two types of sprains in the early postinjury period by the method described.