胫骨髓内钉入路治疗胫骨干骨折的临床进展

胫骨干骨折是最常见的长骨骨折,对于不稳定的胫骨骨折,胫骨髓内钉因其独特的优势逐渐成为首选治疗方式。当前对于胫骨干髓内钉入路主要分为髌骨上入路和髌骨下入路。髌骨上入路放置髓内钉时,患肢半伸直位有利于胫骨干骨折的复位与固定,但可能会造成髌骨关节面损伤。髌骨下入路患肢屈曲位可能会造成胫骨干复位的丢失,进而影响患者的预后。因此,胫骨髓内钉置入不同入路可能造成不同临床结局,会对临床结局造成不同的影响。目前对于胫骨髓内钉最佳入路仍然存在争议,针对最近发表的相关文献我们对胫骨髓内钉入路及其优缺点进行讨论综述。     

半伸直位髓内钉联合空心螺钉固定治疗胫骨下1/3螺旋形骨折合并后踝骨折的疗效研究

摘要 目的：探讨半伸直位髓内钉联合空心螺钉固定治疗胫骨下1/3螺旋形骨折合并后踝骨折的疗效。方法：回顾性分析2016年10月至2020年6月期间中国人民解放军陆军第七十三集团军医院收治的60例胫骨下1/3螺旋形骨折合并后踝骨折患者的临床资料,男47例,女13例,年龄18～71岁,平均（53.15±4.06）岁,致伤原因：车祸伤27例,摔伤21例,运动伤12例。根据髓内钉置钉方式不同将其分为两组,半伸直组采用半伸直位髓内钉联合空心螺钉固定（30例）,标准组采用标准髓内钉联合空心螺钉固定（30例）,所有患者术后随访1年。比较两组手术时间、术中出血量、骨折愈合时间、踝关节功能、膝关节功能、疼痛程度、并发症的差异。结果：半伸直组手术时间短于标准组（P<0.05）,两组术中出血量、骨折愈合时间比较无统计学差异（P＞0.05）。两组术后美国足踝外科协会（AOFAS）评分、Karlsson踝关节功能（KAFS）评分、美国纽约特种外科医院(HSS)评分均呈增高趋势（P<0.05）,视觉模拟评分法（VAS）评分均呈降低趋势（P<0.05）,半伸直组术后12周、术后1年VAS评分均低于标准组（P＜0.05）,HSS评分高于标准组（P＜0.05）。两组并发症发生率比较无统计学差异（P＞0.05）。结论：采用半伸直位髓内钉联合空心螺钉固定治疗胫骨下1/3螺旋形骨折合并后踝骨折患者,与标准髓内钉联合空心螺钉固定比较,安全性和促进踝关节恢复的效果相当,且手术用时更短,患者术后疼痛更轻,膝关节功能改善更明显,在治疗中更具优势。     

两种不同内固定手术对髌骨骨折患者术后膝关节功能恢复的影响

目的:探讨两种不同的手术方式(钛制空心钉结合张力带内固定手术)对髌骨骨折患者的临床疗效和安全性比较。方法:选择2016年6月-2017年10月治疗的髌骨骨折患者72例作为对象,使用随机数字表,随机分为对照组(n=36)和观察组(n=36)。对照组给予常规的克氏针张力带内固定进行手术,观察组则使用空心钉张力带进行固定。治疗后对患者效果进行统计和评估,比较两组患者的术后骨折的愈合时间,功能恢复(最大屈曲角度),髌骨评分以及并发症等指标。结果:根据不同的治疗方式后,观察组(空心钉张力带固定组)在骨折的愈合时间,功能恢复,髌骨评分以及并发症等比较指标中较对照组均有显著优势,其结果具备统计学意义(P<0.05)。结论:将钛制空心钉结合张力带内固定手术用于髌骨骨折与传统的克氏针张力带固定方法相比较,具有操作简便,骨折愈合率高,功能恢复确实,并发症发生率低等诸多优点,值得在临床中进一步推广应用。     

两种内固定方法治疗髌骨骨折术后关节面对合情况的比较

目的：比较改良张力带钢丝内固定和传统张力带钢丝内固定治疗髌骨横行骨折术后关节面对合的效果。方法：2007年3月至2011年9月,分别采用胥氏张力带钢丝内固定和改良张力带钢丝内固定且随访超过1年的髌骨横行骨折的患者64例,术中分别采用胥氏张力带钢丝内固定和改良张力带钢丝内固定治疗,随访时行膝关节X线摄片检查,观察关节面对合情况,比较两种治疗方法所致关节面台阶样错位是否大于2mm的差异。结果：64例患者均获得随访,随访时间8~18个月,平均13.2个月,骨折端均愈合,两组Lysholm评分比较无统计学意义（P=0.665）;胥氏张力带钢丝内固定组和改良张力带钢丝内固定组分贝出现1例（3.1%）和7例（21.9%）关节面台阶征,两组关节面台阶征的发生率比较差异有统计学意义（P=0.036）。结论：胥氏张力带钢丝固定法使髌骨骨折术后固定作用加强,关节面对合更好,能有效预防因台阶征引起的创伤性关节炎的发生。     

顺行髓内钉、逆行髓内钉及锁定加压钢板内固定治疗股骨远端骨折的对比研究

摘要目的：探讨顺行髓内钉、逆行髓内钉及锁定加压钢板内固定3种方法治疗股骨远端骨折患者的疗效。方法：对2011年1月至2012年12月间我院收治的101例股骨远端骨折进行临床随机分组手术,分别在手术中使用顺行髓内钉、逆行髓内钉以及锁定加压钢板内固定。对三组患者手术时间、术中出血量以及切口长度等一般情况进行比较分析,同时采用Harris评分系统对三组患者术后恢复情况进行分析比较。结果：经过手术治疗后,逆行髓内钉组Harris评分显著高于其他两组（P〈0．05）。另外,逆行髓内钉组手术过程短、出血量少、手术切口小,上述指标与其他两组比较均有统计学意义（P〈0．05）。结论：股骨远端骨折行逆行髓内钉治疗的疗效优于顺行髓内钉以及锁定加压钢板内固定,具有手术时间短、术中出血少、切口小等优点,能够有效提高术后膝关节功能的恢复,值得临床推广使用。     

尺骨鹰嘴截骨和内外侧入路非截骨入路治疗肱骨髁间骨折的效果比较分析

目的:比较尺骨鹰嘴截骨和内外侧非截骨入路治疗肱骨髁间骨折的效果。方法:前瞻性选取2016年9月至2018年9月在本院进行治疗的76例肱骨髁间骨折患者作为研究对象,按照数字表法随机分为截骨组和非截骨组各38例,截骨组采用尺骨鹰嘴截骨入路进行治疗,非截骨组采用内外侧入路非截骨入路进行治疗。比较两组患者手术时间、术中出血量、术后24 h出血量、X线暴露时间,术后12个月骨折延迟愈合、尺神经麻痹、关节挛缩、骨关节炎等并发症的发生率以及疗效。结果:截骨组手术时间、术中出血量、术后24 h出血量、X线暴露时间明显低于非截骨组,差异均有统计学意义(P0.05)。截骨组并发症的发生率为13.16%,非截骨组并发症发生率为26.32%,两组比较差异无统计学意义(P0.05)。截骨组优良率为84.21%,非截骨组优良率为71.05%,两组比较差异无统计学意义(P0.05)。截骨组C1、C2、C3型肱骨髁间骨折术后肘关节评分优良率分别为78.57%、88.23%、85.71%,非截骨组C1、C2、C3型肱骨髁间骨折术后肘关节评分优良率分别为86.66%、73.33%、62.50%,非截骨组C1型肱骨髁间骨折术后肘关节评分优良率略高于截骨组,截骨组C2、C3型肱骨髁间骨折术后肘关节评分优良率略高于非截骨组,但两组不同AO分型优良率比较差异无统计学意义(P0.05)。结论:肱骨髁间骨折患者应用尺骨鹰嘴截骨入路手术较肱三头肌内外侧非截骨入路手术具有一定的临床优势,可显著减少手术时间、术中出血量、术后24h出血量以及术中X线照射时间,并且术后肘关节功能恢复较好,在粉碎较为严重的C2、C3型肱骨髁间骨折中推广使用。     

Shoulder joint loadings in post total hip replacement surgery patients during assisted walking: The influence of the crutch setup

A crutch is prescribed to permit the patient to walk safely and independently immediately after total hip replacement (THR) surgery. Purpose of this study is to evaluate the influence of the crutch setup on upper limbs biomechanics, including shoulder joint kinematics and kinetics parameters that will be evaluated to detect possible differences related to the crutch length.Thirty patients were randomly assigned to elbow flexed (EF) or elbow extended (EE) forearm crutch setup. Subjects were asked to walk on the laboratory path, instrumented with motion tracking system and force platforms. Spatiotemporal gait parameters, crutch ground reaction force (GRF) and crutch displacement (measured as the relative distance between the crutch position on the floor and the shoulder joint center), were evaluated. A three-dimensional (3D) biomechanical model was implemented to determine shoulder joint kinematics and kinetics during crutch walking.Results showed that the stride length significantly decreased, and base of support width increased for the EF group when compared to the EE group. Crutch forces and distance to the body significantly decreased in the EE group. Furthermore, shoulder joint moments in all planes of motion, vertical and lateral forces were significantly reduced in the EE group.The present study showed that crutch setup influenced performance and upper limb loading during walking, with EE setup allowing a more stable walking and reducing stress on the shoulder joint when compared to the EF setup. Results may help therapists in rationalizing crutch length adjustments for patients after THR surgery.     

空心钉张力带钢丝联合内固定治疗髌骨骨折的临床疗效

目的:探讨空心钉张力带钢丝联合应用内固定在髌骨骨折患者中的临床疗效及安全性。方法:收集于我院就诊的150例髌骨骨折患者,随机分为实验组和对照组,各75例。对照组患者行钢丝环扎内固定术,实验组患者给予空心钉张力带钢丝内固定术。观察并比较两组患者骨折愈合时间、手术时间、临床治疗优良率以及患者的并发症的发生情况。结果:与对照组相比,实验组患者的骨折愈合时间显著缩短,但手术时间较长,治疗优良率较高,并发症发生率较低,差异均具有统计学意义(P0.05)。结论:与钢丝环扎内固定术比较,空心钉张力带钢丝联合应用治疗髌骨骨折的临床疗效较好,安全性更高。     

FEMORAL SHAFT FRACTURES—A Study of Closed Reduction and Open Treatment

A comparative study was made of 58 cases of closed femoral shaft fractures treated by skeletal traction, and 24 cases of closed femoral shaft fractures treated by open reduction with internal fixation.Although complications occurred in some cases, intramedullary nailing appeared to be the most satisfactory method, resulting in primary union, in decreased time of recumbency and time in hospital, in earlier ambulation and in less residual disability.Success of intramedullary nailing depends largely upon adequate training or experience of the surgeon in the technical operative aspects of the procedure and in postoperative management.Placing supplemental autogenous iliac bone chips at the fracture site in closed femoral fractures in which intramedullary nailing is performed appears to enhance callus formation and bony consolidation.Skeletal traction should be utilized on all patients whose general physical condition does not permit operative intervention.     

Olecranon orientation as an indicator of elbow joint angle in the stance phase,and estimation of forelimb posture in extinct quadruped animals

Reconstruction of limb posture is a challenging task in assessing functional morphology and biomechanics of extinct tetrapods, mainly because of the wide range of motions possible at each limb joint and because of our poor knowledge of the relationship between posture and musculoskeletal structure, even in the extant taxa. This is especially true for extinct mammals such as the desmostylian taxa Desmostylus and Paleoparadoxia. This study presents a procedure that how the elbow joint angles of extinct quadruped mammals can be inferred from osteological characteristics. A survey of 67 dried skeletons and 113 step cycles of 32 extant genera, representing 25 families and 13 orders, showed that the olecranon of the ulna and the shaft of the humerus were oriented approximately perpendicular to each other during the stance phase. At this angle, the major extensor muscles maximize their torque at the elbow joint. Based on this survey, I suggest that olecranon orientation can be used for inferring the elbow joint angles of quadruped mammals with prominent olecranons, regardless of taxon, body size, and locomotor guild. By estimating the elbow joint angle, it is inferred that Desmostylus would have had more upright forelimbs than Paleoparadoxia, because their elbow joint angles during the stance phase were approximately 165° and 130°, respectively. Difference in elbow joint angles between these two genera suggests possible differences in stance and gait of these two mammals. J. Morphol. 2009. © 2009 Wiley‐Liss, Inc.     

The fixion proximal femur nailing system: biomechanical properties of the nail and a cadaveric study

The treatment of choice for early mobilization of hip fracture is surgery, which traditionally employs side plates and screws or intramedullary nails. We examined the biomechanical properties of a new proximal femoral nail system. The new expandable Fixion proximal femur nailing (PFN) system, made of stainless-steel alloy, consists of a nail, a peg and an anti-rotation pin. Upon positioning, the nail and peg are expanded to their maximal diameter. The current biomechanical study investigated: nail bending strength and stiffness, fatigue properties and hip peg strength. A cadaveric study that determined the effect of the expandable peg on the femoral head included subsidence testing, pull and torsion testing and intra-osseous pressure (IOP) measurements before and after expansion. Biomechanical properties of the new nail met ASTM F384 guideline requirements. The cadaver study yielded equivalent results for the pullout test between the peg and the hip screw, but found the peg superior in the torsion strength test. IOP during peg insertion and expansion was substantially lower than the threshold pressure that causes avascular necrosis. The biomechanical tests found the new system to be safe and able to provide good abutment of the nail to the bone. We conclude that the Fixion PFN system proved to be an effective proximal femur fracture fixation device.     

弹性髓内钉和钢板固定对儿童股骨干中段骨折的疗效比较

目的:观察并比较弹性髓内钉(ESIN)与钢板固定(PF)治疗儿童股骨干中段骨折的临床疗效。方法:选择2013年2月至2016年12月我院收治的股骨干中段骨折患儿90例,依据治疗方法不同分为ESIN组和PF组。ESIN组(n=45)采用弹性髓内钉固定,PF组(n=45)采用钢板固定,比较两组患者手术时间、手术切口、术中失血量、术后切口引流量等手术指标,随访评估患者住院时间、完全负重时间、骨折愈合时间;按Flynn评定标准比较两组患者的最终治疗结果。结果:两组患者术中失血量、术后引流量比较差异无统计学意义(P0.05),ESIN组患者手术切口显著小于PF组(P0.05),手术时间、透视时间、完全负重时间均显著短于PF组(P0.05),临床疗效明显优于PF组(P0.05)。结论:与钢板固定比较,弹性髓内钉在手术时间、透视时间显著短于钢板固定,临床疗效明显优于钢板固定,可作为儿童股骨干骨折内固定的首选材料。     

Shape of articular surface of crocodilian (Archosauria) elbow joints and its relevance to sauropsids

The determination of area and shape of articular surfaces on the limb bones of extinct archosaurs is difficult because of postmortem decomposition of the fibrous tissue and articular cartilages that provide the complex three‐dimensional joint surfaces in vivo. This study aims at describing the shape of the articular cartilages in the elbow joints of six crocodilian specimens; comparing its structure with that of four birds, three testudines, and five squamates; and comparing the shapes of the surfaces of the calcified and the articular cartilages in the elbow joints of an Alligator specimen. The shapes of the articular cartilages of crocodilian elbow joint are shown to resemble those of birds. The humerus possesses an olecranon fossa positioned approximately at the midportion of the distal epiphysis and bordering the margin of the extensor side of the articular surface. The ulna possesses a prominent intercotylar process at approximately the middle of its articular surface, and splits the surface into the radial and ulnar cotylae. This divides the articular cartilage into an articular surface on the flexor portion, and the olecranon on the extensor portion. The intercotylar process fits into the olecranon fossa to restrict elbow joint extension. Dinosaurs and pterosaurs, phylogenetically bracketed by Crocodylia and Aves (birds), may have possessed a similar olecranon fossa and intercotylar process on their articular cartilages. Although these shapes are rarely recognizable on the bones, their impressions on the surfaces of the calcified cartilages provide an important indication of the extensor margin of the articular surfaces. This, in turn, helps to determine the maximum angle of extension of the elbow joint in archosaurs. J. Morphol., 2010. © 2010 Wiley‐Liss, Inc.     

扩髓更换髓内钉治疗髓内钉固定后股骨干肥大性骨不连

目的:评价扩髓更换髓内钉治疗髓内钉固定后股骨干肥大性骨不连的临床疗效及手术适应症。方法:自1998年4月至2009年6月采用扩髓更换髓内钉治疗11例髓内钉固定后股骨干肥大性骨不连,其中男9例,女2例,年龄23-61岁。平均36.2岁,骨折部位在股骨上1/3者2例;中1/3者6例;下1/3者3例,原始骨折Winquist-Hansen分型:I型2例,II型3例,III型4例,IV型2例。结果:11例患者均获随访,时间:11～56个月,平均27.4个月,2例患肢短缩1 cm。另4例未获得骨性愈合,3例再次采用附加钢板合并自体髂骨植骨,1例远端锁钉动力化,再次干预后获得骨性愈合,愈合时间6～16个月,平均8.3个月。结论:扩髓更换髓内钉是治疗髓内钉固定后股骨肥大性骨不连的传统方法,基于力学稳定和临床观察,更适用于股骨中段骨不连。     

伤椎置钉联合短节段内固定与单纯短节段固定治疗胸腰椎爆裂性骨折的比较研究

目的:比较伤椎置钉联合短节段内固定与单纯短节段固定治疗胸腰椎爆裂性骨折的临床疗效、固定效果及其对患者炎症反应和脊髓损伤的影响。方法:选取2014年3月到2016年12月期间我院收治的胸腰椎爆裂性骨折患者94例,根据手术方法的不同将患者分为伤椎置钉组(40例)和短节段内固定组(44例)。短节段内固定组患者采用单纯后路短节段椎弓根螺钉内固定进行治疗,伤椎置钉组采用伤椎置钉联合后路短节段椎弓根螺钉内固定进行治疗。比较两组患者的手术时间、术中出血量、住院时间、伤椎前沿高度比、Cobb’s角、伤椎椎体楔形变角、视觉模拟评分(VAS)和Oswestry功能障碍指数(ODI),炎性因子指标、脊髓损伤指标及术后并发症。结果:伤椎置钉组的手术时间长于短节段内固定组(P<0.05),术后6个月、术后12个月伤椎置钉组的伤椎前沿高度比明显高于短节段内固定组,Cobb’s角、伤椎椎体楔形变角明显低于短节段内固定组(P<0.05),术前、术后1周、术后6个月、术后12个月两组患者的VAS评分和ODI比较差异无统计学意义(P>0.05),术后3 d两组患者血清中IL-1β、IL-6、IL-8、TNF-α和pNF-H、NSE、S100β、GFAP水平比较差异均无统计学意义(P>0.05)。随访期间两组患者均未出现严重并发症。结论:伤椎置钉联合后路短节段椎弓根螺钉内固定可有效改善胸腰椎爆裂性骨折患者的椎体高度、Cobb’s角和伤椎椎体楔形变角,并且不会增加脊髓损伤和机体的炎症反应。     

半髋关节置换治疗高龄老年人不稳定转子间骨折的效果研究

目的:探讨半髋关节置换术治疗老年不稳定性转子间骨折的治疗效果。方法:选择我院骨科2013年1月至2015年2月入院的老年不稳定转子间骨折患者64例,随机分为半髋关节置换组和髓内钉固定组,对两组手术时间、术中出血量、术后并发症、术后髋关节功能恢复状况进行评价。结果:半髋关节置换组手术时间较髓内钉固定组短(P0.05),半髋关节置换组和髓内钉固定组术中出血量、手术后并发症、髋关节功能恢复状况的差异不具有统计学意义(P0.05)。结论:半髋关节置换术治疗老年不稳定性转子间骨折具有较好的临床效果。     

Occult posterolateral rotatory dislocation of the elbow with olecranon fracture in a child: a case report

ABSTRACT: INTRODUCTION: Acute posterolateral rotator elbow dislocation in a child is rare and can be easily misdiagnosed due to immaturity of the epiphysis. This is the first case of occult posterolateral rotator elbow dislocation in combination with an olecranon fracture. We report our experience with this case, which was not diagnosed correctly by plain radiographs. CASE PRESENTATION: An 11-year-old Asian boy suffered severe pain and swelling of his right elbow after his outstretched arm hit a car dashboard in a motor vehicle accident. Plain radiographs showed only a minimally displaced olecranon fracture and a tiny lateral epicondylar avulsion fracture. However, stress radiographs under general anesthesia revealed severe posterolateral rotatory instability. During surgery, we found that the cartilaginous lateral epicondylar apophysis was much larger than the epicondylar fragment on the radiographs. After the lateral epicondylar osteochondral fragment and lateral collateral ligament complex were fixed, the instability disappeared. CONCLUSION: Our experience with this case shows that it is important to check for instability with pediatric elbow fractures, because a tiny avulsion fracture was able to cause severe posterolateral rotatory instability in a child.     

Biomechanical influences of pin placement and elbow angle on hinge alignment and joint distraction of bridged elbow-pin-fixator construct

Joint distraction and mobilization with a hinged external fixator preserves elbow stability and mobility. However, the alignment of both elbow and fixator hinges was the initial prerequisite of the arthrodiatasis technique. The main goal of this study was to numerically evaluate the kinematic influence of the device, surgery, and joint factors on hinge alignment. The kinetic effects of the pins placement and elbow angle on concentric distraction and mobilization were also discussed. A unilaterally hinged elbow-fixator system with a 14 links and 10 degrees-of-freedom was instrumented into a humeroulnar model. The Denavit–Hartenberg method with the homogeneous transformation matrixes was applied to perform kinematic analysis of the linkage system. The predicted results revealed that the concurrence of hinge alignment (i.e., kinematic) and concentric distraction (i.e., kinetic) necessitates two telescopic tubes orthogonal to the elbow hinge. The degrees-of-freedom arrangement of the fixator articulators plays a significant role in hinge alignment. After joint distraction, two hinges might be misaligned due to the difference in the structural rigidity of the pins, fixator, and stiffened elbow. Furthermore, those two prerequisite are interactive and sensitive to elbow angle, fixator design, and pin placement of the bridged elbow-pin-fixator construct. In addition, the ideally concentric distraction might occur only at an elbow angle of 120° owing to the ulnar anatomy. Meticulous planning is necessary for such highly technically demanding surgery.     

A new technique for internal fixation of femoral fractures in mice: impact of stability on fracture healing

Mouse models are of increasing interest to study the molecular aspects of fracture healing. Because biomechanical factors greatly influence the healing process, stable fixation of the fracture is of interest also in mouse models. Unlike in large animals, however, there is a lack of mouse models which provide stable osteosynthesis. The purpose of this study was therefore to develop a technique for a more stable fixation of femoral fractures in mice and to analyze the impact of stability on the process of fracture healing. The new technique introduced herein includes an intramedullary pin and an extramedullary metallic clip. Ex vivo biomechanical analysis revealed a significantly higher implant stiffness of our pin-clip technique when compared with previously described intramedullary fixation techniques. In vivo, we studied the course of healing after the more stable fixation with our pin-clip technique and compared the results with that observed after unstable fixation with the pin-clip technique after cutting the clip. After 2 and 5 weeks of fracture healing radiological analysis demonstrated that the more stable fixation with the pin-clip technique results in a significantly higher union rate compared to the unstable fixation. Torsional stiffness at 5 weeks was almost 3-fold of that measured after unstable fixation. Histomorphological analysis further showed that fractures stabilized with the pin-clip technique healed with a smaller periosteal callus area, an increased fraction of bone and a reduced amount of fibrous tissue. Of interest, the pin-clip fixation showed reliable union after 5 weeks, whereas the unstable pin fixation did not regularly achieve adequate fracture healing. In conclusion, we introduce a novel, easily applicable internal osteosynthesis technique in mice, which provides rotational stability after femoral fracture fixation. We further show that a more stable osteosynthesis significantly improves the process of fracture healing also in mice.     

Orientation and location of the finite helical axis of the equine forelimb joints

To reduce anatomically unrealistic limb postures in a virtual musculoskeletal model of a horse's forelimb, accurate knowledge on forelimb joint constraints is essential. The aim of this cadaver study is to report all orientation and position changes of the finite helical axes (FHA) as a function of joint angle for different equine forelimb joints. Five horse cadaver forelimbs with standardized cuts at the midlevel of each segment were used. Bone pins with reflective marker triads were drilled into the forelimb bones. Unless joint angles were anatomically coupled, each joint was manually moved independently in all three rotational degrees of freedom (flexion–extension, abduction–adduction, internal–external rotation). The 3D coordinates of the marker triads were recorded using a six infra-red camera system. The FHA and its orientational and positional properties were calculated and expressed against joint angle over the entire range of motion using a finite helical axis method. When coupled, joint angles and FHA were expressed in function of flexion–extension angle. Flexion–extension movement was substantial in all forelimb joints, the shoulder allowed additional considerable motion in all three rotational degrees of freedoms. The position of the FHA was constant in the fetlock and elbow and a constant orientation of the FHA was found in the shoulder. Orientation and position changes of the FHA over the entire range of motion were observed in the carpus and the interphalangeal joints. We report FHA position and orientation changes as a function of flexion–extension angle to allow for inclusion in a musculoskeletal model of a horse to minimize calculation errors caused by incorrect location of the FHA.