Extensor Carpi Radialis Longus Tendon Research Articles

Tendon ball arthroplasty and proximal carpal stabilization with tendon graft for advanced Kienbock's disease.

This study reports the surgical technique and outcomes of tendon ball arthroplasty combined with proximal carpal stabilization using the extensor carpi radialis longus tendon for treating advanced Kienbock's disease. The collapsed lunate is excised and a tendon ball inserted as a spacer. A distally based extensor carpi radials longus graft is passed through the scaphoid, tendon ball and triquetrum, reconstructing the proximal carpal row. In total, 16 patients were included and the mean follow-up was 25 months. Pain improved from 5.6 preoperatively to 1.3 postoperatively on a 10-point visual analogue scale. Mean wrist motion improved by 17.8° and grip strength compared with the non-operative side increased by 22.1% on average. Radiographic outcomes demonstrated correction of scaphoid flexion and carpal height ratio. The modified tendon ball arthroplasty may be an alternative wrist salvage procedure for the treatment of advanced Kienbock's disease.Level of evidence: IV.

Prevalence, evaluation, and clinical implications of a reticular tunnel formed by uncharacteristic distal fibers of the abductor pollicis longus

IntroductionVariations in muscles of the pollex are common, and some can elicit significant clinical implications. The abductor pollicis longus (APL) frequently exhibits non-typical morphologies; however, descriptions of uncharacteristic distal fibers from APL (APLudf) that form a reticular tunnel around the tendons of extensor carpi radialis longus (ECRL) and brevis (ECRB) are scarce in current literature. The objective of this study is to investigate the prevalence of APLudf with concurrent report of in situ and cross-sectional gross imaging. MethodsThe distal aspect of 110 APL muscles was examined for APLudf and reticular tunnel formation. Reticular tunnel length was measured over the long axis of the underlying ECRL tendon, and APLudf pennation angle was recorded. Characteristic APL and APLudf examples were photographed in situ, and one example of APLudf was cross-sectioned to show the bony attachment of the atypical fibers in relation to contiguous anatomy. A unique finding of an APLudf accessory tendon inserting onto an accessory abductor pollicis brevis muscle was removed, splayed, and photographed. ResultsAPLudf were present in 65 (59.1%) of upper limbs. The APLudf originated from a free origin over the ECRL and ECRB tendons and a fixed origin from the lateral margin of the distal radius and inserted onto the main APL tendon or an accessory tendon, creating a distinct reticular tunnel around the ECRL and ECRL with a mean length of 20.25 ± 5.55 mm (range = 11.09 mm–36.09 mm) and 12.99° ± 1.44° pennation. All APL muscles displayed one main tendon and at least one accessory tendon which originated solely from APLudf on 43 (39.1%) of the specimens. ConclusionsThe present study suggests the prevalence of APLudf is 59.1% and often occurs bilaterally. The restriction of intersecting movements within the APLudf reticular tunnel could cause ECRL and ECRB tendon inflammation (i.e., intersection syndrome), directly affect respective functions (e.g., radial extension of the wrist, abduction and extension of the thumb), and complicate surgical management in the region. This report may inform educators and healthcare providers when deliberating diagnosis, treatment, and healing of associated forearm, wrist, and pollex conditions.

Retrograde intramedullary nailing of the radius in children: A pilot magnetic resonance imaging study of soft-tissue findings.

Purpose:Unstable forearm shaft fractures in children are preferably treated surgically using elastic stable intramedullary nails. The radius is nailed retrograde from the distal metaphysis. There is a risk of surgery-related soft-tissue complications during the operation. Close evaluation of occult surgery-related soft-tissue lesions has not been possible previously, due to the titanium alloy hardware used in the process. The aim of the present study was to evaluate the potential findings in the surrounding soft tissues after intramedullary nailing of the radius, by using magnetic resonance imaging.Methods:The study population comprised 15 pediatric patients with forearm shaft fractures treated by polylactide-co-glycolide biodegradable intramedullary nails and postoperatively evaluated via magnetic resonance imaging. The main outcome was signal abnormality in any tendon at the entry point postoperatively. Secondarily, other changes in the soft tissues related to nailing were determined. Furthermore, the precise location of the entry point and the anatomic characteristics of the soft-tissue tunnel were described.Results:In total, 5 of 15 patients (33.3%) had transient signal pathology in a tendon postoperatively. Edema around the superficial radial nerve was detected in 13 of 15 patients (86.7%). The most common surgical approach was between the extensor pollicis brevis and the extensor carpi radialis longus tendons, which was applied in 10 of 15 patients (66.7%).Conclusions:One in three patients exhibited transient and occult surgery-related intraparenchymal signal pathology in a tendon, after forearm intramedullary nailing. Caution with surgical prepare of the soft-tissue cleavage is recommended.Level of evidence: IV

Correction of ulnar claw hand – A comparative study of extensor carpi radialis longus (ECRL) and flexor digitorum superficialis (FDS) as the motor unit of choice

Leprosy is a chronic infectious disease caused by M. leprae, with peripheral neuropathy as its most common manifestation. Deformity of the hand is particularly debilitating and the ulnar claw hand is the most common presentation. There are various surgical options available for correcting clawing in Hansen’s disease. In the present study we have tried to identify patient-related factors favouring either Extensor Carpi Radialis Longus (ECRL) or Flexor Digitorum Superficialis (FDS) as the motor unit of choice. Method A comparative study of ECRL (Brand Procedure) and FDS (Stiles–Bunnel) motor tendon transfer in the ulnar claw of hand was carried out. Correction of clawing of fingers was done in 60 ulnar claw hands using transfer of motor units ECRL and FDS. The Z deformity was corrected by 1∕2 FPL to EPL transfer. 12 cases were lost to follow up over the course of 5 years, so 48 cases were followed for up to 2 years, for various activities of daily life and routine work. Conclusion Both the transfers gave equivalent results. No morbid deformity was seen in ECRL transfer except the scar on the donor thigh. FDS transfer is the best reconstructive tendon transfer procedure for correction of ulnar claw hand in manual labourers. For white-collar workers, ECRL transfer should be the choice.

Novel Technique in Late Stage Avascular Necrosis of Lunate: Tendon Interposition and Ligament Reconstruction with ECRL Tendon– A Case Report

Aim: To evaluate clinical and functional results of extensor carpi radialis longus tendon ball interposition for treatment of late stage avascular necrosis of lunate (kienbock’s disease).
 Materials and Methods: Patient with stage 4 kienbock’s disease was treated with excision of lunate and ecrl tendon interposition to fill the cavity of the excised lunate bone. Tendon was split. One half was left in situ and the other was used to fill the cavity by passing it to the scaphoid and triquetrum. This also helps to maintain intercarpal stability. Functions were assessed using grip strength, range of movement of wrist, quick dash and visual analogue score. Radiological examination was performed to assess carpal height ratio and progression of arthritis.
 Results: Long and bulky ecrl tendon acts as a spacer to fill the excised lunate. it also provides scapho lunate and lunate triquetral ligament reconstruction for inter carpal stability.
 Conclusion: ECRL tendon used for interposition with reconstruction seems to be an effective treatment modality for late stage of kienbock’s disease.

Dynadesis for Treatment of Dynamic Scaphoid Instability with 20-Year Results.

Background Even though the scapholunate interosseous ligament is the most common wrist ligament injury, its treatment remains a challenge for hand surgeons. We report on a surgical treatment (Dynadesis) for dynamic scaphoid instability (DSI) with a 20-year follow-up period. Description of Technique Dynadesis utilizes antagonist forearm muscles in order to synergistically provide dynamic stabilization to the scaphoid when the wrist is loaded. It is a tendon-to-tendon transfer with the following two components: 1) Dorsal-The extensor carpi radialis longus (ECRL) is passed through a hole in the reduced, distal scaphoid, providing the scaphoid with an independent extension force. 2) Volar-A dynamic checkrein is created by tension-locking the ECRL tendon around the flexor carpi radialis (FCR) tendon. The portion of the FCR distal to the scaphoid tethers and tightens with contracture of the ECRL and FCR muscles. Patients and Methods Twenty patients (21 wrists) were treated with Dynadesis and reevaluated 20 years later (range: 20-27 years). Results Average grip strength improved by 8 kg. The average wrist flexion-extension arc decreased by 3 ° . Wrist X-rays showed no radiocarpal arthritis. On the Mayo wrist score, 81% reported excellent to good results (average: 89). Pain levels improved by 90%, with 76% of patients reporting no pain. All patients (100%) were satisfied with their results and would recommend the procedure. Conclusions Dynadesis is specifically designed for the treatment of DSI. It avoids the eventual complication of osteoarthritis and does not sacrifice wrist motion. A predictable and satisfactory long-term result is obtainable with correct patient selection based on clinical staging and arthroscopic findings.

Tendon repair with intercalated partial extensor carpi radialis longus tendon graft for chronic extensor pollicis longus tendon rupture.

The main treatment choices for chronic extensor pollicis longus (EPL) tendon rupture consists of tendon transfer and tendon repair with tendon graft. Tendon transfer with extensor indicis proprius (EIP) is currently considered the gold standard treatment which yields predictable and satisfactory results, but potentially compromises the strength of independent extension of the index finger. We propose our method of using a partial extensor carpi radialis longus (ECRL) tendon graft to repair chronic EPL tendon tears. The distal stump of the EPL was located through an incision at the basal joint level. The proximal stump was located through a curved incision at the dorsoradial wrist where the partial ECRL tendon graft was harvested. The tendon graft was subcutaneously transposed, sutured at both ends, and tensioned at full thumb extension with a neutral wrist position. From March 2016 to June 2019, 23 patients (mean age: 59.7 years; mean follow-up: 29.6 months) were retrospectively reviewed. All the patients were followed for a minimum of 12 months. The final total active motion was 93.2% of the contralateral thumb. The mean Quick Disabilities of the Arm, Shoulder and Hand score was 6.0. There was one complication possibly due to poor EPL muscle quality, and the patient was subsequently treated with EIP tendon transfer. Our study showed that using a partial ECRL tendon graft to repair chronic EPL tendon rupture results in satisfactory functional outcomes. The advantages of this method include preservation of EIP function and using the same incision for graft harvesting and tendon repair. This method can be considered an alternative to EIP tendon transfer in patients with high demand for their index finger function.

A novel technique of annular ligament reconstruction using extensor carpi radialis longus tendon fascia: a report of 3 cases

<p class="abstract">Annular ligament is an important stabiliser of radial head. In cases of chronic radial head dislocation, annular ligament reconstruction is warranted to maintain radial head reduction to improve elbow function. We have reported here a novel technique using the fascia overlying extensor carpi radialis longus tendon for annular ligament reconstruction. We reported an average flexion of 130º and full supination in all 3 cases. 2 patients achieved mid pronation and 1 achieved full pronation; comparable with other described techniques. Our novel technique through a single incision has excellent functional outcomes. Additionally, it is simple, cost effective, requires no hardware.</p>

Second Metacarpal Base Avulsion Fracture Due to the Extensor Carpi Radialis Longus Tendon: A Case Report

Fracture avulsion injuries of the extensors of the wrist are not common. The most common mode of injury is forced flexion of the hand and wrist with Extensor Carpi Radialis Longus (ECRL) contraction at the same time. These fractures are generally managed by Open Reduction and Internal Fixation (ORIF) along with repair of the ECRL tendon. This modality of management is associated with less chance of complications, makes the joint more stable and has an overall positive result.

Thumb Carpometacarpal Arthroplasty with Dynamic Suspension Sling Using Extensor Carpi Radialis Tendon.

Background: Despite various treatment methods, complications are reported with ligament reconstruction for thumb carpometacarpal (CMC) arthropathy, such as proximal migration, dorsal subluxation of the first metacarpal base, and hyperextension of the first CMC joint. The flexor carpi radialis (FCR) tendon is, in some cases, too thin to maintain suspension on the first metacarpophalangeal (MCP) joint. We used one-half of the extensor carpi radialis longus (ECRL) tendon instead of the FCR tendon, and compared this method with conventional reconstruction using the FCR tendon. Methods: The procedures were performed during 12 thumb CMC arthropathies. One-half of the ECRL tendon was passed and then wrapped around the intact FCR tendon several times for 6 cases (ECRL group). One-half of the FCR tendon was passed for 6 cases (FCR group). On radiography, we compared the thumb to index finger metacarpal angle (M1M2) and the first MCP angle (P1M1) between groups. Grip strength, pinch strength, and DASH score were also evaluated up to 2 years post-surgery. Results: In the ECRL group, M1M2 and P1M1 1 year post-surgery showed significant improvements compared to those before surgery; they showed no significant difference in the FCR group, although they achieved a peak at 3 months post-surgery in both groups. Both groups showed improvements in other parameters from 3 months to 1 year post-surgery. Conclusions: Postoperative progression of hyperextension of the first CMC joint was significantly reduced in the ECRL group. The ECRL tendon is thicker than the FCR tendon. In addition, the insertion site of the ECRL tendon is at the dorsal side of the second metacarpal, and the tendon can extend from the dorsal side to the volar side to stabilize the first metacarpal. Thumb CMC arthroplasty using one-half of the ECRL tendon is a useful reconstruction method.

Complications of Corrective Osteotomies for Extra-Articular Distal Radius Malunion

Osteotomy of the distal radius for a fracture malunion is a challenging procedure. The purpose of this study was to review a series of osteotomies to determine the type and risk of complications. A retrospective cohort study was performed, including all Kaiser Permanente Southern California patients who were aged 18 years or older between January 1, 2007, and September 25, 2015, and underwent osteotomy for an extra-articular distal radius fracture malunion. Charts were reviewed for demographic data, comorbidities, osteotomy type (hinged vs distraction), implant, and bone graft type. Complications including infection, nonunion, loss of reduction, implant failure, nerve injury, tendon injury, and complex regional pain syndrome were recorded. There were 60 patients who underwent extra-articular osteotomy of the distal radius for malunion during the study period. The mean age was 54 years (range, 21-83 years). There were 24 distraction-type (intervening bone graft) and 36 hinge-type (volar cortical contact maintained) osteotomies. Twenty-five of 60 patients had complications related to the procedure requiring 13 subsequent procedures. There were 7 nonunions and 3 cases of delayed healing at the osteotomy site. One extensor carpi radialis longus tendon laceration resulted from the use of an osteotome. There were 3 delayed extensor pollicis longus (EPL) tendon ruptures after surgery. The distraction-type osteotomy was associated with a greater risk of major complications including nonunion and delayed union. A complication rate of nearly 50% was observed in distal radius osteotomies. Surgeons should be aware of the risk of injury to, or delayed rupture of the EPL tendon associated with these procedures. The risk of nonunion or delayed union is higher in distraction-type compared with hinge-type osteotomies. Low surgeon volume with this procedure may be a contributing factor to the high rate of complications. Therapeutic IV.

Extensor Carpi Radialis Longus Tenodesis Using a Biotenodesis Screw for Treatment of Symptomatic Geissler 2 Scapholunate Dissociation

Treatment of scapholunate dissociation (SLD) depends on the degree of injury. We present our technique of extensor carpi radialis longus (ECRL) tenodesis for Geissler grade 2 SLD and our preliminary results. After arthroscopic confirmation of Geissler grade 2 SLD, we use a single incision and a polyetheretherketone (PEEK) anchor, attaching half of the ECRL tendon to the scaphoid. Preliminary results include improvements in QDASH, QDASH (work) and QDASH (sports/music), a median satisfaction level of 4/5 (satisfied), and a low complication rate. Our method is a safe, reproducible, and effective treatment of symptomatic Geissler grade 2 SLD that has failed nonoperative management, with technical advantages over alternative methods in the literature.

Extensor carpi radialis longus tendon ball interposition arthroplasty for treatment of late-stage Kienböck's disease: Short-term results of a novel technique.

The aim of this study was to evaluate short-term clinical and radiological results of extensor carpi radialis longus (ECRL) tendon ball arthroplasty for treatment of late-stage Kienböck's disease. We retrospectively reviewed data of 19 patients suffering from Kienböck's treated with ECRL tendon ball arthroplasty between December 2014 and December 2016. Patients' clinical functions were assessed using grip strength, range of motion (ROM) of the wrist, QuickDASH, Mayo wrist score, and visual analog scale score. Radiological examination was performed to assess carpal height ratio and progression of arthritis. The median follow-up was 30 months (range, 12-36 months). At final follow-up, ROM of operated wrist was 71% of the nonoperated side. Thirteen (86.6%) patients were pain free. Carpal height ratio was statistically significantly reduced compared with preoperative values. All patients declared their satisfaction with the results due to their preoperative status. ECRL tendon ball arthroplasty is a new and good option for treatment of late-stage Kienböck's disease with low complication rate.

Aberrant course of superficial radial nerve in the forearm: an anatomical variation and its clinical implications

The superficial radial nerve (SRN) is the terminal pure sensory branch of the radial nerve supplying dorsal aspects of the proximal portion of the lateral three and a half digits...

Graft Site Morbidity in Elbow Ligament Reconstruction Procedures: A Systematic Review

Background: It is unclear which tendon harvest for ulnar or lateral collateral ligament reconstruction has the lowest graft site morbidity rate. Purposes: To obtain graft site morbidity rates after tendon harvest for ulnar and lateral collateral ligament reconstruction procedures. Study Design: Systematic review/Meta-analysis. Methods: Studies were eligible if (1) patients had undergone elbow ligament reconstruction procedures; (2) original data for at least 5 patients were available; (3) the article was written in English, German, or Dutch; (4) a full-text article was available; and (5) information about graft site morbidity was available. The review excluded studies about complicated elbow ligament reconstruction procedures due to initial fractures, revision procedures, or circumferential graft techniques; animal studies; (systematic) reviews; and expert opinions. Because the majority of studies were case reports, no selection form or overall scoring system to evaluate methodological quality was used. Results: The review included 619 patients with an ulnar or lateral collateral ligament reconstruction procedure. The autograft types used included palmaris longus tendon (58%), gracilis tendon (24%), semitendinosus tendon (8%), triceps tendon (7%), toe extensor tendon (<2%), plantaris tendon (<2%), extensor carpi radialis longus tendon (<1%), and Achilles tendon (<1%). Conclusion: Graft site morbidity occurred in 1% of the patients after an ulnar or lateral collateral ligament reconstruction procedure. This study did not have enough samples of all the autograft types to conclude that autograft type and graft site morbidity are unrelated.

ECRL Suspension as a Revision Procedure in Failed Resection Arthroplasty of the First Carpometacarpal (CMC-I) Joint

Objective: Resection arthroplasty (RSA) is the standard procedure for first carpometacarpal (CMC-I) joint arthritis and gives excellent results in 95% of patients. There are several reasons explaining the 5% unsatisfying results. To the best of our knowledge, there is no report in the literature concerning revision procedures in failed RSA. The purpose of this retrospective study was to investigate the outcome after extensor carpi radialis longus (ECRL) suspension as a revision procedure in patients with persistent pain due to proximalization and bony impingement of the base of the first metacarpal and the base of the second metacarpal bone and/or the distal scaphoid. Methods: Between 2002 and 2013, 3429 patients with CMC-I arthritis underwent an RSA using the abductor pollicis longus (APL) tendon in our clinic. In the same period of time, we performed 128 revision procedures due to persistent pain following an RSA. Twenty-one of these patients with a mean age of 59 years (range, 51-70 years) demonstrated a proximalization and bony impingement. In these cases, we performed a revision suspension using half of the ECRL tendon. After an average follow-up of 4 years, 15 patients (13 female, 2 male) were available for a clinical and radiological follow-up examination, including range of motion (Kapandji-Score), grip and pinch strength, as well as several clinical tests (eg, grind test). Mayo Wrist Score (MWS) as well as DASH score and patient’s pain (visual analogue scale [VAS], 0-10) were evaluated. Standard radiographs of the wrist and the thumb in two planes were obtained. One of the 6 patients who could not be included in the follow up died, another refused follow-up due to total well-being and 4 patients moved and could not be located. Results: The time between RSA and revision averaged 2 years (range, 1-7 years). Clinical examination showed a positive grind test in 4 patients, and 11 patients remained free of pain. Eleven patients showed full opposition, and 4 patients showed mild restriction of opposition. The Kapandji score averaged 9.4 (range, 8-10), pinch strength averaged 76% of the opposite side. Postoperative MWS was 67, and DASH score was 39 points, whereas MWS was 37 preoperatively. Postoperative pain on VAS was 3 at rest and 5 with activity, whereas it was 8 at rest and 9 with activity previous to revision. Thirteen patients reported major improvement and 2 reported unchanged pain postoperatively. Fourteen patients were satisfied with the final result and would have the same procedure. Radiological evaluation showed a significant improvement in proximalization postoperatively. Twelve patients resumed the original employment, 10 of them performing heavy manual labor. Conclusion: These findings show that ECRL tendon suspension after previous RSA leads to a significant clinical improvement. The operation appears to be an effective revision procedure for patients with persistent pain due to proximalization of the first metacarpal bone and bony impingement following RSA.

A biomechanical study on reconstruction of forearm interosseous membrane using extensor carpi radialis longus combined with radial head replacement for restoring forearm longitudinal stability

To evaluate the effect of reconstruction of forearm interosseous membrane (IOM) using extensor carpi radialis longus combined with radial head replacement for restoring the forearm longitudinal stability. Ten fresh-frozen adult cadaveric forearms were selected, including 8 males and 2 females with a mean age of 38.2 years (range, 29-74 years). Each forearm was treated as following steps: radial head excision (group A), radial head excision+the distal ulnar radial joints separation (group B), radial head excision+the distal ulnar radial joints separation+IOM central band excision (group C), reconstructed IOM with extensor carpi radialis longus tendon (group D), radial head prothesis replacement (group E), and reconstructed IOM with extensor carpi radialis longus tendon+radial head prothesis replacement (group F). The distance between ulna and radius and radioulnar joint displacement were observed under load and non load. The force loading on both ends of specimen was recorded when the radius shifted 5 mm proximally. Restoring the radial length could maintain normal distance between radius and ulna. The interosseous membrance reconstruction could restore the load transmission between radius and ulna. The force loading specimen was (74.507±4.967), (49.227±1.940), (17.827±1.496), (24.561±1.390), (140.247±8.029), and (158.423±9.142）N in groups A, B, C, D, E, and F respectively when the radius shifted 5 mm proximally, showing significant difference among groups (P<0.01). Reconstruction of the IOM with the extensor carpi radialis longus tendon is insufficient to restore the forearm longitudinal stability. Reconstruction using extensor carpi radialis longus tendon combined with radial head replacement may be a new choice for treatment of forearm longitudinal instability.

Sonographic Appearance of the Extensor Carpi Radialis Intermedius Tendon

Figure 1. Transducer positioning for sonographic short-axis (SAX) view of the second dorsal compartment (CPT) with correlative sonographic and magnetic resonance imaging (MRI) images. (A) Transducer (black rectangle) and patient positioning for the sonographic SAX view of the second dorsal CPT. (B) Sonographic correlative image of the second dorsal CPT at the level of the proximal intersection of the first dorsal CPT over the second dorsal CPT. The extensor carpi radialis intermedius tendon (white arrow) is shown in its typical location between and deep to the extensor carpi radialis longus (ECRL) (L) and extensor carpi radialis brevis (B) tendons. Note thickening and hypoechoic heterogeneity of the ECRL tendon consistent with tendinosis. (C) A correlative T2-weighted axial MRI scan of the same patient again shows the extensor carpi radialis intermedius tendon (white arrow) between and deep to the ECRL (L) and extensor carpi radialis brevis (B) tendons. The dotted rectangle represents the relative sonographic field of view represented in image B. LT ¼ Lister’’s tubercle; RAD ¼ radius; ULN ¼ ulnar. (Note: The MRI image was inverted for orientation purposes.) PM R 7 (2015) 789-791

Implanted passive engineering mechanism improves hand function after tendon transfer surgery: a cadaver-based study.

The purpose of this study was to investigate if a new tendon transfer surgical procedure that uses an implanted passive engineering mechanism for attaching multiple tendons to a single donor muscle in place of directly suturing the tendons to the muscle improves hand function in physical interaction tasks such as grasping. The tendon transfer surgery for high median ulnar palsy was used as an exemplar, where all four flexor digitorum profundus (FDP) tendons are directly sutured to the extensor carpi radialis longus (ECRL) muscle to restore flexion. The new procedure used a passive hierarchical artificial pulley system to connect the muscle to the tendons. Both the suture-based and pulley-based procedures were conducted on N = 6 cadaver hands. The fingers' ability to close around four objects when the ECRL tendon was pulled was tested. Post-surgery hand function was evaluated based on the actuation force required to create a grasp and the slip between the fingers and the object after the grasp was created. When compared with the suture-based procedure, the pulley-based procedure (i) reduced the actuation force required to close all four fingers around the object by 45% and (ii) improved the fingers' individual adaptation to the object's shape during the grasping process and reduced slip by 52% after object contact (2.99° ± 0.28° versus 6.22° ± 0.66°). The cadaver study showed that the implanted engineering mechanism for attaching multiple tendons to one muscle significantly improved hand function in grasping tasks when compared with the current procedure.

Tendon Interposition and Ligament Reconstruction with ECRL Tendon in the Late Stages of Kienböck’s Disease: A Cadaver Study

Background. The optimal surgical treatment for Kienböck's disease with stages IIIB and IV remains controversial. A cadaver study was carried out to evaluate the use of coiled extensor carpi radialis longus tendon for tendon interposition and a strip obtained from the same tendon for ligament reconstruction in the late stages of Kienböck's disease. Methods. Coiled extensor carpi radialis longus tendon was used to fill the cavity of the excised lunate, and a strip obtained from this tendon was sutured onto itself after passing through the scaphoid and the triquetrum acting as a ligament to preserve proximal row integrity. Biomechanical tests were carried out in order to evaluate this new ligamentous reconstruction. Results. It was biomechanically confirmed that the procedure was effective against axial compression and distributed the upcoming mechanical stress to the distal row. Conclusion. Extensor carpi radialis longus tendon has not been used for tendon interposition and ligament reconstruction in the treatment of this disease before. In view of the biomechanical data, the procedure seems to be effective for the stabilization of scaphoid and carpal bones.