Extensor Digiti Minimi Research Articles

The use of chimeric musculocutaneous posterior interosseous artery flaps for treatment of osteomyelitis and soft tissue defect in hand.

There is growing evidence of the superior ability of muscular tissue to clear bacterial bone infection. Unfortunately, in the hand, there are almost no small local muscular flaps, and muscular transfers to the hand are mainly microsurgical free transfers. In this report, we present the results of the use of a chimeric posterior interosseous flap including part(s) of the forearm muscles to treat osteomyelitis and soft tissue defect of hand from a series of patients. Four male patients with an average age of 32 years (range 20-46 years), were affected by acute osteomyelitis in hand. Previous fracture fixation with percutaneous K-wires was the cause of bone infection in three case. In one case, the osteomyelitis was a consequence of an open fracture. The bones affected were four metacarpals and one proximal phalanx, all with a minimal cortical defect (from the K-wire) obscuring a larger medullary infection, which required extensive bone and overlying soft tissue debridement, leaving a soft tissue defect to be reconstructed of size ranging from 2 x 4 cm to 5 x 7 cm. The soft tissue defects were due to concomitant superficial infection and consequent debridement. All patients were treated with bone debridement and a chimeric posterior interosseous flap, which included part of the extensor digiti minimi and/or extensor carpi ulnaris to fill the intramedullary canal of the bones. No fixation of bone was necessary. The skin paddle of the flaps ranged from 2 x 5 cm to 5 x 6 cm, replicating the defect area, plus a teardrop tail of skin circa 1.5 cm wide and as long as the pedicle of the flap. The muscular components of the flaps used to fill the intramedullary canals ranged from 1 x 1 x 1.5 cm to 1.5 x 1.5 x 4 cm. All flaps survived and osteomyelitis resolved in all cases without major complications. At the final follow-up at 16 months (range 12-26 months), assessment of the hands using TAM, Power Grip and Key Pinch Strength measurements and, where appropriate, Kapandji scores, demonstrated satisfactory hand function. The chimeric posterior interosseous flap including part of the muscles of the forearm may be a robust solution for augmenting the flap bulk and may be used in cases of severe osteomyelitis of the hand.

Arthroscopy of the distal radioulnar joint

The aim of the procedure is to visualize the proximal pouch of the DRUJ, the joint surfaces of the sigmoid notch and the ulnar head, the convexity of the ulnar head and the proximal ulnar side surface of the triangular fibrocartilage complex (TFCC). Arthroscopy of the distal radioulnar joint is applied for the evaluation of joint pathologies in ulnar-sided wrist pain, especially in cases without diagnostic findings in standard X‑rays and MRIs and arthroscopically assisted procedures. In vertical extension, two portals of the wrist are created on the dorsal side of the DRUJ between the extensor digiti minimi and extensor carpi ulnaris tendons. By insertion of asmall joint arthroscope via these portals visualization of the ulnar head, the sigmoid notch, the proximal pouch of the DRUJ and the proximal surface of the TFCC is accomplished. Arthroscopy of the DRUJ is ararely and not routinely performed procedure for the diagnosis and therapy of ulnar-sided wrist pain. It is technical demanding with aflat learning curve and anatomy-related obstacles. Acomplete view of the joint is not always accessible. Rare complications are injuries of the extensor digiti minimi tendon, as well as contusion or sectioning of the transverse branch of the dorsal branch of the ulnar nerve. In distinct cases, this procedure offers important additional information about the distal radioulnar joint. The procedure is especially valuable for the detection of proximal TFCC injuries that are missed otherwise.

Predicting Tendon Tissue Grafting Source From the Extensors of Long Fingers: A Systematic Review of Cadaveric Studies

Background: The use of tendon tissue for transfer and grafting is a common practice in hand surgery. Many local tendons are usually used, mainly that of the palmaris longus muscle. However, this tendon could be absent in up to 46%. Extra slips of the extensor digitorum communis (EDC) and extra tendons such as the extensor indicis (EI) and the extensor digiti minimi (EDM) could be valuable sources for tendon tissue. Methods: A systematic review was conducted to quantify the proportion of extra slips in relation to each tendon and extra tendons in relation to each long finger. The aim is to better predict the location of tendon tissue sources on the dorsum of the hand in reconstructive surgery. Results: Based on 39 studies including 7847 hands, the cumulative frequencies of extra slips and extra tendons and the association between double-slip frequency and ancestry were as follows: (1) the little finger showed the highest cumulative frequency of extra slips (96.54%), followed by the ring (37.5%), long (30.6%), and index (9.5%) fingers; (2) the index with its EI and its variants and the little finger with its EDM bear by far the highest cumulative frequency of extra tendons (≈100%); and (3) double slips are found to be rare in Indian populations, most prevalent in Japanese populations, more prevalent in the index and little fingers of Caucasians, and more prevalent in the ring fingers of Middle Eastern populations. Conclusions: Knowledge of the frequencies of extra slips for each long extensor tendon and extra tendons for each long finger along with their prevalence in different populations would improve: (1) location prevision of tendon source for tendon grafting; and (2) surgical planning while supporting a patient-centered approach. Evidence-based hand anatomy would have a major potential to contribute to the practice of an evidence-based hand surgery. Predicting the possible tendon sources that could be present on the dorsum of the hand is thought to be very valuable for hand surgeons. In addition and from an evolutionary perspective, we hypothesized that the observed significantly higher frequency values of the double-slip and triple-slip types of the EDC of the ring finger, EDC of the little finger, and EDM might indicate a natural selection tendency for a higher independence of the former digits in the future evolution of the human hand.

Irreducible Galeazzi Fracture-Dislocations.

Fractures of the radial shaft with disruption of the distal radial ulnar joint (DRUJ) or Galeazzi fractures are treated with reduction of the radius followed by stability assessment of the DRUJ. In rare instances, the reduction of the DRUJ is blocked by interposed structures requiring open reduction of this joint. The purpose of this study is to review all cases of irreducible Galeazzi fracture-dislocations reported in the literature to offer guidelines in the diagnosis and management of this rare injury. A search of the MEDLINE database, OVID database, and PubMed database was employed using the terms "Galeazzi" and "fracture." Of the 124 articles the search produced, a total of 12 articles and 17 cases of irreducible Galeazzi fracture-dislocations were found. The age range was 16 to 64 years (mean = 25 years). A high-energy mechanism of injury was the root cause in all cases. More than half of the irreducible DRUJ dislocations were not identified intraoperatively. In a dorsally dislocated DRUJ, a block to reduction in most cases (92.3%) was secondary to entrapment of one or more extensor tendons including the extensor carpi ulnaris, extensor digiti minimi, and extensor digitorum communis, with the remaining cases blocked by fracture fragments. Irreducible volar dislocations due to entrapment of the ulnar head occurred in 17.6% of cases with no tendon entrapment noted. In the presence of a Galeazzi fracture, a reduced/stable DRUJ needs to be critically assessed as more than half of irreducible DRUJs in a Galeazzi fracture-dislocation were missed either pre- or intraoperatively.

The Relative Contribution to Small Finger Abduction of the Ulnar Versus Radial Slip of the EDM: Implications for Tendon Transfers.

The extensor digiti minimi (EDM) tendon is commonly divided into a radial slip (EDM-R) and an ulnar slip (EDM-U). To our knowledge, the degree to which each EDM slip concomitantly abducts the small finger with active extension has not been formally tested. This study sought to characterize the comparative contributions of finger abduction inherent to each slip of the EDM to observe the sequelae of active small finger extension following transfer of the contralateral slip. Eighteen fresh-frozen cadaveric hands were used in this study. Starting with the hand in resting position, a controlled traction of 10 N was applied to each slip of the EDM tendon. The range of small finger abduction with respect to the fixed ring finger was recorded utilizing infrared reflective markers tracked through the range of motion using a digital video camera. The mean abduction of the small finger when the radial slip of the EDM tendon was tested was 13.33° (95% confidence interval [CI]: 10.10°-16.55°), which was significantly different ( P ≤ .001) than small finger abduction produced by the ulnar slip of the EDM, with a mean of 23.72° (95% CI: 19.40°-28.04°). Given the fact that the ulnar slip of the EDM tendon is shown to be the major contributor of aberrant abduction with active small finger extension, as traction on this slip produces almost twice as much abduction as the radial slip, the EDM-U is the ideal donor graft with respect to tendon transfers of the EDM.

The Relationships Between Surface Measurements and Underlying Tendon Autograft Length for Upper Extremity Reconstructive Surgery

The availability of tendon grafts is an important consideration for successful upper extremity reconstructive surgery, including flexor or extensor tendon reconstructions, tendon transfers, and ligament reconstructions. Graft selection is based on availability, expendability, ease of harvest, and length. Given variations in patient height and extremity length, existing average values may provide suboptimal insight into actual tendon lengths available. The purpose of this study is, therefore, to pursue a method of estimating available donor tendon lengths based on easily measured anatomical surface landmarks. Thirty cadaveric upper and lower extremity limbs were dissected and the length of commonly harvested tendon grafts including the palmaris longus, extensor indicis proprius, extensor digiti minimi, plantaris, and second long toe extensor was measured. Surface forearm length (from finger tip to cubital fossa) and surface fibular length (from lateral malleolus to fibular head) were also measured. Correlations between surface measurements and underlying tendon lengths were analyzed, and linear models were generated that predicted tendon length as a function of surface measurements. Surface measurements were correlated with underlying tendon length (R= 0.46 - 0.66). Linear models could predict tendon lengths based on surface measurements. A ratio of donor tendon length compared with the limb segment measured was established for each tendon and can be applied to estimate donor tendon length. For the upper extremity tendons, the multipliers for the palmaris longus, extensor indicis proprius, and extensor digiti minimi were 0.51, 0.20, and 0.18, respectively. Lower extremity tendon ratios for the plantaris and extensor digitorum longus were 0.69 and 0.60, respectively. Although length of available donor tendon can be a limiting variable at the time of surgery, surgeons may be better able to estimate underlying tendon lengths using easily obtained superficial measurements. Information obtained from these cadaveric measurements may aid in preoperative planning in hand and upper extremity surgery.

Transfert des branches nerveuses de l’Extensor Digiti Minimi et de l’Extensor Carpi Ulnaris sur les nerfs moteurs intrinsèques. Une étude histologique sur cadavre

BackgroundIn cases of high ulnar and median nerve palsy, result of nerve repair in terms of intrinsic muscle recovery is unsatisfactory. Distal nerve transfer can alleviate the regeneration time and improve the results. Transfer of the extensor digiti minimi (EDM) and extensor carpi ulnaris (ECU) nerve branches to the deep branch of ulnar nerve (DBUN)/recurrent branch of median nerve (RMN) at wrist had been used to restore intrinsic hand function but, incomplete recovery occurred. The axon count at the donor nerve has a strong influence on the final results. HypothesisThis cadaveric study aims to analyses the histology of this nerve transfer to evaluate whether these donor nerves are suitable for this transfer or another donor nerve may be considered. Materials and methodsTen cadaveric upper limbs dissected to identify the location of the EDM, ECU, RMN and DBUN. Surface area, fascicle count, and axon number was determined by histological methods. ResultsThe mean of axon number in the EDM, ECU, RMN and DBUN branches was 5931, 7355, 30,960 and 35,426, respectively. In this study, the number of axons in the EDM and ECU branches was 37 % (13,281/35,426) of that in the DBUN. Also, the number of axons in the EDM and ECU branches was 42 % (13,281/30,960) of that in the RMN. ConclusionThe axon count data showed an unfavorable match between the EDM, ECU and DBUN/RMN. Therefore, it is suggested that another donor nerve with higher axon number to be considered. Type of studyCadaver study (histological study).

Transfer of extensor digiti minimi and extensor carpi ulnaris nerve branches to the intrinsic motor nerve branches: A histological study on cadaver

BackgroundIn cases of high ulnar and median nerve palsy, result of nerve repair in term of intrinsic muscle recovery is unsatisfactory. Distal nerve transfer can alleviate the regeneration time and improve the results. Transfer of the extensor digiti minimi (EDM) and extensor carpi ulnaris (ECU) nerve branches to the deep branch of ulnar nerve (DBUN)/recurrent branch of median nerve (RMN) at wrist had been used to restore intrinsic hand function but, incomplete recovery occurred. The axon count at the donor nerve has a strong influence on the final results. HypothesisThis cadaveric study aims to analyses the histology of this nerve transfer to evaluate whether these donor nerves are suitable for this transfer or another donor nerve may be considered. Materials and methodsTen cadaveric upper limbs dissected to identify the location of the EDM, ECU, RMN and DBUN. Surface area, fascicle count, and axon number was determined by histological methods. ResultsThe mean of axon number in the EDM, ECU, RMN and DBUN branches was 5931, 7355, 30960 and 35426, respectively. In this study, the number of axons in the EDM and ECU branches was 37% (13281/35426) of that in the DBUN. Also, the number of axons in the EDM and ECU branches was 42% (13281/30960) of that in the RMN. ConclusionThe axon count data showed an unfavorable match between the EDM, ECU and DBUN/RMN. Therefore, it is suggested that another donor nerve with higher axon number to be considered. Type of studyCadaver study (histological study).

Clinical application of dorsal metacarpal artery composite flap for coverage of tendon and skin defects of the fingers

Objective To discuss the surgical techniques and treatment outcomes of one-stage repair of complex soft tissue and extensor tendon defect of the fingers by transferring dorsal metacarpal artery flap that includes extensor indicis proprius (extensor digiti minimi proprius) tendon and dorsal cutaneous nerve. Methods From April 2013 to September 2015, 6 cases of middle finger dorsal complex tissue defect were managed with dorsal metacarpal artery composite flap transfer for skin coverage, extensor tendon repair and sensory restoration. The flap size that covered these defects ranged from 6.0 cm×2.0 cm to 7.0 cm×3.0 cm.The donor site was directly closed.Passive functional exercise was initiate done one week postoperatively and lasted for 4 to 6 weeks. Results All 6 flaps survived completely. All the patients were follow-up for 3 to 13 months with an average of 8.2 months. Sensation of the flaps recovered to S3 level. Two-point discrimination was 7 to 10 mm while the mean value was 8.6 mm. The color, texture and contour of the flaps were good. Mobility of the hand was satisfactory. Conclusion Dorsal metacarpal artery composite flap transfer is a reliable way to cover complex tissue defects on the dorsum of fingers. It has consistent vascular anatomy, affords extensor tendon and cutaneous nerve reconstruction along with skin coverage, shortens treatment time, and improves outcomes without added risks. Key words: Surgical flaps; Finger injuries; Metacarpal artery; Compound tissue flap

The clinical effect of tendon repair for tendon spontaneous rupture after corticosteroid injection in hands: A retrospective observational study.

Corticosteroid injections for hand tendinitis can lead to a rare significant complication of tendon spontaneous rupture. However, only sporadic cases were reported in the literature before. This study was designed to gauge the clinical effect of tendon repair in patients of tendon spontaneous rupture after corticosteroid injection and analyze our experience.This was a retrospective observational study of 13 patients (8 women and 5 men) operated between July 2011 and December 2015 for tendon spontaneous rupture after corticosteroid injection. Demographic data, clinical features, imaging data, and surgical treatments were carefully reviewed.The average age was 52.308 ± 15.381 years (range 29–71). The average injection times were 2.538 ± 1.664 times (range 1–6). The average rupture time (after last injection) was 10.923 ± 9.500 weeks (range 3–32). Nine patients were treated by tendon suture (69% of cases), and 4 patients were treated by tendon grafting (31% of cases). All patients received follow-up in our outpatient clinic. The sites of the tendon rupture (15 tendons of 13 patients had involved) include extensor pollicis longus (6 tendons, 40% of cases), extensor digiti quinti and extensor digiti minimi (4 tendons, 27% of cases), ring finger of extensor digitorum communis (3 tendons, 20% of cases), and middle finger of extensor digitorum communis (2 tendons, 13% of cases). Two patients who had tendon adhesion (15% of cases) were treated by tendon release. One patient who had tendon rerupture (8% of cases) was treated by tendon grafting. No patient had complications of infections, vascular, or nerve injury.Tendon spontaneous rupture is a serious complication after corticosteroid injection for tendinitis. Rigid standard of corticosteroid injection is very important. Magnetic resonance imaging was contributory to preoperative assess tendon defect and can be used to monitor healing quality of tendons during the follow-up.

Extensor Digiti Minimi Transfer for the Treatment of an Unstable Metacarpophalangeal Joint in Thumb Polydactyly Without Thenar Atrophy.

Dear Sir, As treatments for the laxity of metacarpophalangeal (MCP) joint in hypoplastic thumb, joint capsular plication, free tendon graft or MCP arthrodesis have been performed [1]. In addition, transfer of abductor digiti minimi [2] or ring finger flexor digitorum superficialis [3] have been used to provide thumb opposition and restore MCP joint stability. In the present case, we used extensor digiti minimi (EDM) transfer to treat MCP joint instability due to ulnar collateral ligament laxity in a patient with thumb polydactyly without thenar muscle atrophy. An 11-year-old girl who was naturally right thumb polydactyly with floating ulnar thumb had a thumb plasty at the age of five. But she was bothered by an unstable MCP joint due to ulnar collateral hypoplasia (Fig. 1a). Six years later from primary operation, she underwent a second surgery to improve joint instability and outer appearance of the thumb. The MCP joint instability was corrected by an EDM transfer, which involved fasting the end of the transferred tendon to the ulnar side of the MCP joint at the bottom of proximal phalanx and at the metacarpal head (Fig. 2). At 10 months postoperatively, the appearance of the thumb was improved and the MCP joint was stable (Fig. 1b). The EDM transfer procedure was initially reported for restoration of thumb adduction in ulnar nerve paralysis [4], but MCP joint stability could be achieved by changing the distal tendon insertion as this case. We consider there are some advantages to this procedure: 1) the MCP joint achieves maximum stability in the opposite position, because the tension of the transferred EDM tendon increases with the increase in the angle of opposition, 2) the mobility of the MCP joint is not impaired, 3) the strength of side pinch could be increased by increasing the thumb adduction force. On the other hand, the disadvantages of this procedure include that this transfer would position thumb in extension and adduction, and a decrease in the extension force of the little finger. The former demerit barely mattered in actuality, because we think the tension of transferred EDM is not strong in the rest position.

Role of Interosseous Recurrent Artery Perforators in the Posterior Interosseous Artery Flap.

The Posterior Interosseous Artery flap is a fasciocutaneous flap based on the Posterior Interosseous artery which lies invested by the fascial septum between the Extensor carpi ulnaris and Extensor Digiti Minimi where it gives off septocutaneous branches that spread out on the deep fascia to form longitudinal fascial arcades as well as supply the deep extensors. The conventional flap based on these perforators is restricted to the middle-thirds of the dorsum of forearm. Preservation of the perforators from the Interosseous Recurrent Artery by proximal ligation of the Interosseous Recurrent Artery and by protecting the index septum prolongation carrying the perforators of IRA can help us to recruit larger tissue in the flap. A total of 20 clinical cases and 10 cadaveric dissections were done to objectively define this technique.

Extensor Tendon Repairs Zones 4 to 8

Objective/Hypothesis: This audit purposed to compare the early active motion (EAM) and immediate controlled active motion (ICAM) regimes postextensor tendon repair in zones 4 to 8. No previous comparison of these regimes was found. In 2005, Wyndell Merritt et al. introduced the ICAM regime, which includes a wrist and yoke splint. The ICAM regime was presented at International Federation of Societies of Hand Therapy (IFSHT) 2013 and was trialed at our unit from 2015. Materials and Methods: A prospective audit was conducted between November 2015 and November 2016 of all extensor zones 4 to 8 patients. Patients were treated by either EAM or ICAM regime dependent on patient suitability, staff skills, and regime criteria. Demographics, outcome, and complication data were recorded. Results: Totally, 51 patients and 63 digits (70% index or middle) were audited. Twenty-six patients were in the EAM group (mean age, 34 years) and 25 in the ICAM group (mean age, 43 years). Of the EAM patients, 21 had a single digit (9 with multiple tendons affected either extensor indicis proprius [EIP]/ extensor digiti minimi [EDM]), 3 patients had 2 digits, 1 patient had 3 digits, and 1 patient had 4 digits affected. Of the ICAM patients, 23 had a single digit affected (4 multiple tendons), and the remainder had 2 digits affected. Injury zone was consistent with EAM:ICAM; zone 4, 5:5; zone 5, 17:18; and zone 6, 4:2. Days from injury to repair was 1 to 5 except for 3 delayed presentations, mean EAM was 2.5 and ICAM was 4.3. Mean days from repair to therapy was 2.9 for EAM and 2.5 for ICAM patients. In the EAM group, 5 patients were transferred to peripheral hospitals, 9 did not attend their appointments, and 1 patient with 4 digits involved was excluded from analysis to allow direct comparison between groups. For the remainder the mean therapy, attendances was 6.8 (range, 3-19) over 8.6 weeks. In the ICAM group, 1 patient transferred and 4 DNA’d. For the remainder the mean therapy, attendances were 5 (range, 2-9) over 7.6 weeks. Two range of motion (ROM) outcomes were used to allow comparison with other studies. Results for EAM:ICAM groups for total active motion were as follows: excellent, 5:9 and good, 6:11; and Millers: excellent, 4:9; good, 5:8; and fair, 2:3. No ruptures presented, but 6 EAM patients experienced scar tethering. At 6 weeks, 5 EAM patients returned to light work duties. At 5 days, 2 ICAM patients returned to light duties and a further 11 with yoke at 4 weeks. The remaining data were not captured. Despite audit limitations of opportunistic regime allocation and demographic variation, it adds valuable data to advancing extensor tendon rehabilitation. Conclusions: Our audit supports the growing evidence that the ICAM regime with low-profile, low-cost splints provides good/excellent outcomes with no complications, fewer therapy attendances, and supports early return to work. In response to the literature and an audit presented at British Association of Hand Therapists (BAHT) conference 2015 involving a yoke-only regime with good/excellent outcomes and no ruptures, we have progressed to a yoke-only ICAM regime and continue to audit the results. Despite the favorable outcomes, there is no level 1 evidence of the ICAM regime. A multicenter clinical trial is planned.

Bilateral anatomical variations of the hand extensors

Background: The purpose of this paper is to describe an anatomical variation of the hand extensor on the little finger of the right hand which receives four tendons, condition unknown, as it is the first case reported so far in the literature. The human extensor tendons of hand often display an array of variations. Awareness of the anatomy and variations of the extensor tendons on the dorsum of the hand is necessary not only for the anatomist but also for surgeons when considering tendons for hand surgery, tendon rerouting or transplants. Materials and Methods: Bilateral anatomical variation in the upper limb was found during routine dissection in a 75-year-old male cadaver in the Morphology Laboratory at the University of Pamplona. The variations were recorded and photographed. Result: In the left hand the extensor digitorum there was a single tendon to the index, double tendon to the middle, triple tendon to the ring finger, a single tendon to the little finger or digiti minimi. The extensor digiti minimi has double tendon. In the right hand the extensor digitorum there was a single tendon to the index, triple tendon to the middle finger, triple tendons to the ring finger, a double tendon to the little finger. The extensor digiti minimi has double tendon. The little finger receives four tendons, 2 of extensor digitorum and 2 of extensor digiti minimi. The dorsum of the left hand and right showed juncturae tendinum type 2, between the extensors tendons in the 3rd intermetacarpal space; type 3, between the extensors tendons in the 4th inter metacarpal space. Conclusion: The presence of multiple tendons may alter the kinematics around the site of attachment to the phalanx. Knowledge of anatomical variations and normal anatomy of the extensor tendons, may be helpful while performing graft and tendon transfer operations.Bangladesh Journal of Medical Science Vol.15(2) 2016 p.278-282

Wrist Pain due to Abnormal Extensor Carpi Ulnaris Tendon.

Pain arising from lesions in the extensor carpi ulnaris (ECU) is known to occur mainly due to tenosynovitis, tendon rupture, and subluxation or dislocation of the ECU tendon [1,2]. However, anomalies of the ECU tendon itself and the surrounding extensor retinaculum are also possible factors contributing to the impairment of function at the dorso-ulnar aspect of the wrist and little finger [2,3]. We report a case in which an abnormal ECU tendon slip was revealed during exploration of the wrist. A 28-year-old right-handed female neurosurgeon visited our clinic due to dorso-ulnar wrist pain in her dominant hand for six months. The pain was exacerbated during wrist motion, especially during forearm supination for handling the needle holders in the operating field. A physical examination revealed no sensory changes and no specific signs, including the Phalen and Finkelstein tests. Radiographic studies also showed no problems such as joint subluxation. The hand showed a slight tender swelling of the ECU tendon around the wrist. With the suspicion of tenosynovitis, steroid injection into the sixth compartment was performed. However, the pain did not respond to medical treatment. Electrodiagnostic studies revealed no abnormalities. On exploration, we found the abnormal insertion of an additional ECU tendon slip into the radial inner side of the sixth compartment (Fig. 1). After simple excision of the entire abnormal ECU tendon slip, her symptoms improved. Fig. 1 The abnormal insertion of an additional extensor carpi ulnaris (ECU) tendon slip into the radial inner side of the sixth compartment. The ECU tendon is enclosed in the sixth compartment of the extensor retinaculum and various anomalies of the ECU tendon have been reported [2,3]. The prevalence of an accessory tendinous slip arising from the ECU tendon has been reported to be 10% to 34% [2,4], and Barfred and Adamsen [3] noted that the accessory tendinous slip of the ECU was sometimes connected with the extensor digiti minimi. Nakashima classified accessory slips into three types according to the insertion point of the main tendon to the fifth metacarpal bone: type A, on the base along with the main tendon; type B, on the midsection; and type C, on the head [2]. The case presented here belonged to type A. The average width of the slips has been reported to range from 1–1.53 mm [2,3], while the presented case showed a slip 1.5 mm in width and 2 cm in length. Taleisnik et al. [5] observed that the transverse fibers of the medial wall of the sixth compartment extend proximally to become confluent with the epimysium of the ECU, and are reinforced by the linea jugata, which normally prevents ECU tendon subluxation during full supination. Since the ECU tendon is exposed to maximal traction when the forearm is supinated, we believe that her wrist pain was induced by repetitive and excessive supination-pronation activity, which might otherwise remain non-symptomatic given usual movement patterns. Anatomical variations of the ECU may affect diagnostic and surgical procedures involving the dorso-ulnar aspect of the wrist. During surgery performed on the ECU, the surgeon must be aware of the possible existence of an accessory tendinous slip that may cause ECU lesions to persist.

Surgical Anatomy of the Radial Nerve at the Elbow and in the Forearm: Anatomical Basis for Intraplexus Nerve Transfer to Reconstruct Thumb and Finger Extension in C7 − T1 Brachial Plexus Palsy

Background C7 - T1 palsy results in complete loss of finger motion and poses a surgical challenge. This study investigated the anatomy of the radial nerve in the elbow and forearm and the feasibility of intraplexus nerve transfer to restore thumb and finger extension. Methods The radial nerves were dissected in 28 formalin-fixed upper extremities. Branching pattern, length, diameter, and number of myelinated fibers were recorded. Results Commonly, the branching pattern (from proximal to distal) was to the brachioradialis, extensor carpi radialis longus, superficial sensory proximal to the lateral epicondyle, extensor carpi radialis brevis, supinator, extensor digitorum communis, extensor digiti minimi, extensor carpi ulnaris, abductor pollicis longus, extensor pollicis brevis, extensor pollicis longus, and extensor indicis distal to the lateral epicondyle. Conclusions Branches to the brachioradialis, extensor carpi radialis longus, and supinator can be transferred to the posterior interosseous nerve to restore hand movement in patients with C7 - T1 brachial plexus palsies; the supinator branch is probably the best choice in this regard.

Variant Superficial Branch of Radial Artery along with Supplementary Tendons on the Dorsum of the Hand and Their Surgical Implications.

Variations of radial artery, in both its course and branching pattern in the anatomical snuffbox, are clinically significant for the plastic surgeons, cardiologists, and radiologists. Reports on its abnormal high origin and subsequent superficial course have been well documented. Herein, we report an unusual superficial branch of the radial artery given off before its entry into the palm by passing between the two heads of first dorsal interosseous. It eventually divided into princeps pollicis and radialis indicis arteries at the first web space of palm as a unique vascular variation. Apart from this, in the present case, the tendon of extensor digiti minimi and of extensor indicis divided into two parts. The split tendons of extensor digiti minimi were inserted to the dorsal digital expansion of the digitus minimus. However, lateral tendon of split extensor indicis was inserted along with the tendon of extensor digitorum to the index finger and the medial one was inserted along with the tendon of extensor digitorum to the middle finger. Unusual superficial branch of radial artery on the dorsum of the hand is vulnerable for an iatrogenic injury during surgical approaches in the region. Supplementary extensor tendons on the hand are one of the potential causes for the tenosynovitis.

Effect of simultaneous stretching of the wrist and finger extensors for lateral epicondylitis: a gross anatomical study of the tendinous origins of the extensor carpi radialis brevis and extensor digitorum communis

BackgroundPulling the wrist into flexion with the elbow in extension and forearm in pronation has been used as the stretching technique of wrist extensors for lateral epicondylitis. Simultaneous stretching of the fingers in addition to the wrist flexion has also been applied. However, the mechanism of this simultaneous stretching has not been clarified. This study is designed to clarify the mechanism underlying this simultaneous stretching technique based on the anatomical features of the origins of the extensor carpi radialis brevis (ECRB) and extensor digitorum communis (EDC). MethodsThirty-nine arms from formalin-embalmed Japanese human specimens were dissected. The features of the origins of the ECRB and EDC were macroscopically observed, and the locations of each origin on the lateral epicondyle were measured. ResultsThe ECRB had a long and wide, purely tendinous origin which originated from the anterior slope of the lateral epicondyle. The tendinous origin of the index finger of the EDC (EDC-IF) arose from the posterior aspect of the ECRB tendinous origin, with a coexisting muscular portion observed at the level of the proximal forearm. The middle finger of the EDC (EDC-MF) had a short tendinous origin with an associated muscular portion and originated proximo-laterally to the origin of the ECRB on the lateral epicondyle. In addition, the muscular origin of the EDC-MF arose on the superficial and posterior aspect of the ECRB tendinous origin. In contrast, the ring and little fingers of the EDC originated from the tendinous septum of the extensor digiti minimi and extensor carpi ulnaris, and had no connection with the ECRB tendinous origin. ConclusionsOn the basis of our anatomical findings, simultaneous stretching of the wrist extensors by wrist, index and middle fingers flexion could provide stretching force to both the tendinous origins of the ECRB and EDC through the EDC-IF and EDC-MF.

Rice Body Tenosynovitis without Tuberculosis Infection after Multiple Acupuncture Procedures in a Hand.

Rice Body Tenosynovitis without Tuberculosis Infection after Multiple Acupuncture Procedures in a Hand.

Changes to Muscle T₂after Single-finger Exercise Measured with 0.2T MR Imaging.

We constructed an arm holder for muscle exercise from a forearm-shaped plastic shell and magnetic resonance (MR) imaging position markers and determined the echo time (39 ms) for T₂-weighted spin-echo MR imaging from T₂values of the exercised (50 ms) and resting (32 ms) muscle at 0.2 tesla. The smallest detectable muscle was the extensor digiti minimi muscle (cross-sectional area 25 mm²). This combination could be useful to monitor finger exercise in patients undergoing physical therapy.