Innervation and vascular supply of the first dorsal interosseous muscle and palmar interosseous muscle of the index: An anatomic descriptive study.

INTRODUCTION: The first dorsal interosseous muscle (FDI) and palmar interosseous muscle of the index (P2I) are essential for the strength and mobility of the index finger. This study aims to describe the course of the deep branch of the ulnar nerve (DBUN) and the blood supply to these muscles. MATERIAL AND METHODS: An anatomical cadaver study was carried out with 14 upper limbs from fresh, non-embalmed cadavers. All limbs were filled with an equal amount, based on weight, of colored silicone and diluent that was combined and catalyzed with 5% curing agent. The location of the DBUN's termination was specified relative the carpometacarpal joint. Every artery supplying either muscle was identified and documented. RESULTS: The DBUN had a slightly convex path, distal to the hook of the hamate and penetrated the FDI muscle at an average 41% of the second metacarpal length. An average of 1.3 branches to the P2I and 2.6 branches to the FDI were found. Four artery pedicles coming from the deep palmar arch supply the FDI with an average of one consistent and exclusive pedicle to the FDI and three pedicles heading to the P2I. According to the classification of Mathes and Nahai, the FDI has a type 2 blood supply and the P2I has a type 3 blood supply. CONCLUSION: In-depth knowledge of the vascular network supplying the FDI and P2I muscles and the course of the DBUN is essential when the DBUN is damaged or when dissecting these muscles for index pollicization.

Anatomy of the ulnar nerve in the posterior compartment of the upper arm: Relationships with the triceps brachii muscle.

The aim of our descriptive anatomical study was to clarify the relationships between the ulnar nerve and the triceps brachii muscle in the posterior compartment of the upper arm. This study involved 30 fresh adult upper limbs. In all specimens, the ulnar nerve crossed from the anterior to posterior compartment in a space formed by the medial intermuscular septum and muscle fibers of the triceps' medial head. This transition zone was located an average of 126mm (115-135mm) proximal to the start of the ulnar groove. In the posterior compartment, the nerve descended vertically, and its anterior side was attached to the posterior side of the septum. Its posterior and lateral sides were covered by muscle fibers from the medial head. Its medial side was always free meaning that the nerve did not penetrate through the medial head. The other heads of the triceps muscle had no direct interactions with the ulnar nerve within this compartment. During its posterior course, the nerve was accompanied by the superior ulnar collateral artery. The ulnar nerve did not give off any branches in the upper arm.

Functional results of displaced proximal humerus fractures in children treated by elastic stable intramedullary nail.

PURPOSE: Displaced proximal humerus fractures within the pediatric population can be treated by elastic stable intramedullary nailing (ESIN). The main objective of our study is to evaluate functional outcome of the displaced proximal humeral fractures treated by ESIN within the pediatric group using a standardized evaluation scale. The secondary goal is to compare functional outcome of epiphyseal and metaphyseal injuries and functional outcome of children younger and older than 10 years of age. MATERIALS AND METHODS: From March 2010 to December 2011, 27 children had been treated surgically using ESIN for displaced fractures at the proximal extremity of the humerus. These fractures were displaced and closed without neurovascular insult. Patients were followed radiographically and clinically on a regular basis. After hardware removal, the functional outcomes had been homogeneously assessed by using the French edition of the QuickDash(®) evaluation scale. The descriptive statistics including mean, standard deviation, and confidence interval have been realized. RESULTS: We included 27 children who were operated on consecutively (10 boys, 17 girls). The mean age at the time of operation is 11.2 ± 2.7 years (range 7.1-15.9). The mean angulation is 55.9° ± 20.3° (range 20-90). The mean apposition is 52.8 % ± 33.1 (range 10-100). The mean follow-up period is 15.2 ± 5.6 months (range 6.1-28.5). Results were considered good for children between 7.1 and 15.9 years old with epiphyseal and meataphyseal fractures. The mean QuickDash(®) score is 2.0 (range 0-6.5), with 14 cases showing a score of 0 (58.3 %), 2 cases with 4.3 (8.3 %), 4 cases with 4.5 (16.7 %), and 4 cases with a score of 6.5 (16.7 %). Ranges of movement were preserved. The patients regained their daily and sportive activity over the time without pain or discomfort. CONCLUSION: Our study showed a good outcome of functional results within a pediatric population who had a sustained displaced proximal humeral fracture and treated by ESIN. Using a standardized evaluation scale is recommended in order to be able to evaluate the patients in a homogeneous manner.

Scaphotrapeziotrapezoid joint loading during key pinch grip before and after trapeziometacarpal arthroplasty: a cadaver study.

In a previous cadaver study, we directly measured the load acting on the trapeziometacarpal joint for increasingly greater key pinch forces. We noted that the joint load ranges from 2 kg to 4 kg during progressively greater key pinch from 0.5 kg to 1.5 kg. Using the same experimental approach, the aim of the current study was to measure and compare the load acting on the scaphotrapeziotrapezoid joint for the same levels of isometric key pinch force, and how it changes after trapeziometacarpal arthroplasty. We performed a cadaver study using 7 fresh-frozen, unembalmed adult forearms and hands (2 right and 5 left). Thumb pinch was simulated by loading the main actuator tendons involved in the key pinch grip (i.e., adductor pollicis, flexor pollicis longus, extensor pollicis longus, extensor pollicis brevis and abductor pollicis longus tendons). Measurements were made inside the joint using a force-sensing resistor sensor (Tekscan® FlexiForce™ force sensor). Before the trapeziometacarpal joint surgery, median load values recorded in the scaphotrapeziotrapezoid joint were 1.2 kg (IQR, 1.0-1.4), 1.6 kg (IQR, 1.6-2.5) and 2.4 kg (IQR, 2.3-3.4) during 0.5 kg, 1 kg and 1.5 kg key pinch, respectively. After the trapeziometacarpal arthroplasty, median joint contact forces did not change significantly relative to the original configuration. Our findings indicate that the loads measured in the scaphotrapeziotrapezoid joint during a simple key pinch are in fact lower than those measured inside the trapeziometacarpal joint. After trapeziometacarpal arthroplasty, the values are similar with no increase in load, suggesting that clinically asymptomatic scaphotrapeziotrapezoid radiographic involvement may not be a contraindication to arthroplasty.

Reconstruction of the distal radius using a double-barrel vascularized fibula flap: A case series.

Treatment of distal radius tumor sometimes requires sacrificing the epiphysis. We propose adding to currently available reconstruction options a technique using a double-barrel vascularized fibula flap fixed distally to the first carpal row, conserving midcarpal mobility. We monitored 4 cases of Campanacci III giant-cell tumor and 2 cases of osteosarcoma. After en-bloc tumor resection, a double-barrel vascularized fibula flap was lodged distally in the scaphoid and lunate and proximally in the radius. Follow-up was clinical and radiological, using DASH, PRWE and MSTS functional scores. At a median 3 years' follow-up, there were no cases of recurrence or non-union. Median ranges of motion were 23° flexion, 28° extension, 90° pronation and 62° supination. Median grip strength proportional to the contralateral side was 67%. Median DASH and PRWE functional scores were respectively 13.7 and 17 points. Median MSTS was 83%. Although this technique is challenging, with difficulties in double-barrel flap placement and in pedicle plication, the double-barrel vascularized fibula flap provided a stable and mobile wrist.

The INCA® implant to treat isolated scaphotrapeziotrapezoid osteoarthritis: Preliminary results at a minimum 2 years' follow-up.

We report results with the INCA® distal scaphoid pole resurfacing implant anchored within the scaphoid for isolated scaphotrapeziotrapezoid osteoarthritis. Thirty-five implants in 27 patients (mean age, 69 years) were retrospectively included with a minimum follow-up of 2 years. Outcome criteria were pain (VAS), PROMs (QuickDASH, PRWE and MMWS), wrist motion, pinch and grip strength, and radiographic assessment. The average follow-up was 4.6 years. There was a significant improvement in pain, PROMs, grip and pinch strength. Radial deviation and wrist extension showed slight but significant postoperative decrease (-4° for both). Dorsal intercalated segment instability (DISI) was significantly improved postoperatively (7 cases versus 21 preoperatively). There were 2 cases of implant loosening (6%) within the first 10 months: 1 keel malpositioning and 1 insufficient postoperative immobilization. These findings suggest that the INCA® implant is an effective and reliable medium-term solution for isolated scaphotrapeziotrapezoid osteoarthritis. By restoring scaphoid length and gliding on the trapeziotrapezoid surface, the implant contributes to restoring normal bone alignment of the wrist.

Trapeziometacarpal joint loading during key pinch grip: A cadaver study.

To our knowledge, no study has directly measured the loads in the trapeziometacarpal joint during an isometric key pinch. The aim of this study was to measure the load acting on the trapeziometacarpal joint for increasingly greater key pinch forces (0.5 kg-1.5 kg). We performed a cadaver study using 10 fresh-frozen, unembalmed adult forearms and hands (5 right and 5 left). Thumb pinch was simulated by loading the main actuator tendons involved in the key pinch grip (i.e., adductor pollicis, flexor pollicis longus, extensor pollicis longus, extensor pollicis brevis and abductor pollicis longus tendons). Measurements were made inside the joint using a force-sensing resistor sensor (Tekscan® FlexiForce™ force sensor). All specimens were tested twice in a row in the same condition. The median load values recorded in the trapeziometacarpal joint were 1.9 kg (IQR 2.2-1.5), 3 kg (IQR 3.4-2.7) and 4.1 kg (IQR 4.4-3.9) during 0.5 kg, 1 kg, and 1.5 kg key pinch, respectively. For each specimen, similar load values were observed during both loading trials. Our findings indicate that the loads measured directly in the trapeziometacarpal joint during a simple key pinch are materially lower than those estimated in biomechanical models of the thumb (generally greater than 10 kg for 1 kg of applied force) probably due to intersubject variability. This pilot study will serve as a basis for further studies, for example, comparing biomechanical thumb models and experimental measurements under the same set-up conditions.

Pollicization in the treatment of congenital severe hypoplasia and aplasia of the thumb: a systematic review.

Pollicization of the index is the treatment of choice for severe hypoplasia and aplasia of the thumb. After a historical overview, we present a systematic review of this procedure. The main steps of this procedure were reported by Dieter Buck-Gramcko in 1971 and are still relevant nowadays. Many refinements have been described over the last decades by different surgeons to address limitations related to bone stock, musculotendinous structures and skin incisions. However, considering the complexity of this procedure and the results in the literature, the functional and esthetic outcomes can still be improved thanks to basic research. Pollicization of the index is rarely done and is one of the most demanding surgical procedure in hand surgery.

First dorsal interosseous muscle transfer to restore opposition of the new thumb after index pollicization: anatomical description of an original technique and case report.

Index pollicization in severe thumb hypoplasia or aplasia in children or for the reconstruction of a mutilated thumb in adults is a rare and technically demanding procedure. Weakness of the new thumb is routinely reported after index pollicization. An inappropriate position of the first dorsal interosseous muscle (FDIM) can partly explain this strength deficit. Here, we report an original anatomical study on FDIM transfer for reanimation of the new thumb's opposition function and its clinical application. An anatomical study was carried out on three upper limbs from fresh, non-embalmed adult cadavers. We demonstrated the feasibility of an FDIM transfer pedicled on the proper FDIM artery and the deep branch of the ulnar nerve. The proximal FDIM insertions were sutured to the lateral border of the flexor retinaculum to recreate the superficial thenar musculature. This procedure was performed on a 52-year-old man who was referred to us with swelling on his hand. We discovered a myxoid inflammatory fibroblastic sarcoma of the thumb that required proximal thumb amputation while preserving the base of the first metacarpal. To our knowledge, this is the first description of FDIM pedicled flap transfer during an index pollicization procedure among an adult population. However, in severe thumb hypoplasia or aplasia cases, this procedure is limited by the size and anatomical variations of the neurovascular structures among a population affected by radial longitudinal deficiency.

Trapeziometacarpal joint ligament reconstruction in early stages of first carpometacarpal joint osteoarthritis.

Trapeziometacarpal joint ligament reconstruction is a surgical option in the early stages of thumb basal joint arthritis when the joint is painful and unstable without chondropathy. Arthroscopy is invaluable here to ensuring the joint surfaces are intact, which is often underestimated by radiography. The Eaton-Littler procedure using a distally pedicled flexor carpi radialis slip has been studied the most in this context. This reconstruction provides pain relief while slowing the rapid development of osteoarthritis.

Coverage of soft tissue defects in the thumb: Essential flaps in daily practice.

Coverage of soft tissue defects in the thumb involves a variety of techniques ranging from simple second-intention healing to skin grafting with or without dermal substitutes, to local homodigital or heterodigital flaps and partial toe transfers. The arsenal in terms of skin coverage and especially flaps is very diverse. Our objective is not to make an exhaustive catalog of all the technical possibilities described in the literature, but rather to present in detail the options we have adopted in our daily practice. For each of these techniques, we present the rules for their implementation (anatomical bases, surgical techniques) and their topographical indications.

Scaphotrapeziotrapezoid arthrodesis for isolated osteoarthritis: results at a mean 8 years' follow-up.

The aim of this retrospective study was to report medium- to long-term outcome of scaphotrapeziotrapezoid (STT) arthrodesis with staple fixation to treat painful isolated osteoarthritis (OA). Twenty-one consecutive patients (22 wrists) who had undergone STT arthrodesis were retrospectively reviewed by an independent examiner. Clinical and radiological evaluation was performed. At a mean follow-up of 8 years (range 2-20 years), pain levels were significantly decreased, and functional scores were significantly improved. Grip and pinch strength were 86% and 82% of those of the contralateral side. Wrist range of motion in flexion-extension and radial-ulnar deviation was significantly less than on the contralateral side at last follow-up (104° vs. 131° and 38° vs. 55°, respectively). Non-union was found on X-ray in 4 wrists (18%), but in 2 cases showed as partial non-union on CT, with complete scaphotrapezial consolidation; 1 of the 4 wrists required surgical revision. Another patient was re-operated on for symptomatic external staple displacement without non-union. There were 8 cases (36%) of radiographic narrowing of the styloscaphoid joint space; contact between the staple and styloid was found in all 8 cases. Four patients (18%) had narrowing of the scaphocapital joint space; protrusion of the proximal part of the staple into the joint space was noted in all 4 wrists. No differences were found for the radioscaphoid, capitolunate and scapholunate angles before and after surgery. STT arthrodesis with staple fixation to treat isolated STT OA led to a significant reduction in pain, with improved strength and functional scores. To avoid styloid impingement, we recommend systematic styloidectomy. Complete non-union seems to be overestimated on radiographs. Partial non-union with scaphotrapezial union should not be considered as a complication. LEVEL OF EVIDENCE: IV.

Comparison of two radiographic landmarks for centering the trapezial component in total trapeziometacarpal arthroplasty.

We performed a retrospective review of standard anteroposterior and lateral radiographs of the thumb in 80 patients, to compare two radiographic landmarks, in terms of mediolateral bone support, for centering the trapezial component in total joint arthroplasty. On anteroposterior view, we identified the distal articular surface of the trapezium and trapezium width, and defined the two midpoints as radiographic landmarks for positioning a 9-mm trapezial cup. Mean trapezium width was significantly greater than the distal articular surface of the trapezium, and the midpoints did not match. Thus, after positioning simulated 9-mm prosthetic cups centered on each landmark, the residual radial bone distance was significantly greater using the landmark based on trapezium width. The mean value was 33% greater with this landmark, and the minimum value was 2.1 mm, compared to 0.2 mm using the landmark based on the distal articular surface. Our study thus suggested that the midpoint of the trapezium width is the more relevant radiographic landmark for centering the trapezial prosthetic cup in total joint arthroplasty, by preserving better bone stock on the radial side without depleting the ulnar side. On an intraoperative anteroposterior fluoroscopic view, this landmark could be used to check cup positioning.

Assessment of trapezial prosthetic cup migration: A biomechanical study.

We performed a biomechanical study using 60 Sawbones® rigid foam blocks of two simulated densities (osteoporotic, n = 30 and non-osteoporotic, n = 30) and 10 cadaveric trapezium bones from fresh-frozen, unembalmed adult cadaver hands to assess the trapezial prosthetic cup migration with progressively greater compression loads (10-40 kg). Two cups from the Touch® prosthesis were compared: 9-mm conical cup and 9-mm spherical cup. Uniaxial compression tests were carried out using an MTS Criterion® Series 40 Electromechanical Testing System. Cup migration was measured in millimeters (mm) at 10, 20, and 40 kg of compression load. Median cup migration values were similar in the cadaveric trapezium bones and Sawbones® non-osteoporotic blocks, and higher in the Sawbones® osteoporotic blocks. In the cadaveric trapezium bones and the Sawbones® non-osteoporotic blocks, migration values were less than or equal to 0.1 mm for 10 and 20 kg loads; it was 0.2 mm for 40 kg load. In the Sawbones® osteoporotic blocks, migration values were less than or equal to 0.3 mm for 10 and 20 kg loads; it was 0.4-0.5 mm for 40 kg load. There was no significant difference between the two cup shapes in both cadaveric trapezium bones and Sawbones® non-osteoporotic blocks. In Sawbones® osteoporotic blocks, the largest difference between the two cup shapes was 0.1 mm for loads up to 40 kg, which corresponded to our measurement accuracy. Our findings indicate that the trapezial component of total trapeziometacarpal joint arthroplasty undergoes very weak migration for axial compression loads up to 40 kg, presumably below the threshold of clinical relevance. The cup shape did not have an obvious influence; however, low bone mineral density may result in greater cup migration.

A new capsulotomy-based dorsal approach to the wrist: A cadaver study.

Using a cadaver study, we described a new dorsal approach to the wrist joint using a "U-shaped with proximal base" capsulotomy. Six fresh adult cadaveric wrists were dissected after intra-arterial silicone injection. We did a dorsal approach to expose the dorsal joint capsule. It was then possible to identify the dorsal radiocarpal and intercarpal ligaments, the dorsal radiocarpal and intercarpal arterial arches, the dorsal branch of the anterior interosseous artery and the terminal branch of the posterior interosseous nerve. Wrist arthrotomy was done using our capsulotomy. In each dissected capsular flap, we always found the individual ligament, vascular, and nerve structures, implying they were intact over their trajectories. The mean surface area of the articular exposure was 945 mm2 (range 725-1102 mm2) allowing easy access to the carpal bones and the radiocarpal and midcarpal joint spaces. This surgical approach to the wrist is technically feasible and avoids damaging the dorsal extrinsic ligaments fibers. Keeping the vascularization intact could improve capsular healing, while preserving innervation could maintain wrist proprioception.

Radiological evaluation of ulnar thumb metacarpophalangeal ligament reconstruction for chronic thumb instability in cadavers.

Various techniques have been described to restore metacarpal stability in the thumb. Ligament reconstruction techniques that position the bone tunnels in a triangular configuration, with the apex proximally, are optimal for stabilizing the metacarpophalangeal (MCP) joint, while preserving the thumb's range of motion. Using an interference screw ensures this reconstruction is as strong as the native ligament. Our purpose was to evaluate a new technique designed to treat cases of chronic thumb instability. We created metacarpal instability in 10 fresh cadaver forearms by sectioning the ulnar collateral ligament (UCL). Ulnar thumb MCP ligament reconstruction (UTMP) was performed in five thumbs and Littler reconstruction in the other five. Radiographic analysis was performed after ligament transection and after ligament reconstruction to compare MCP angles on posterior-anterior (MCPFA) and lateral views (MCPLA), and to evaluate MCP congruence and sesamoid bone parallelism. After UCL transection, thumb instability was present in all cadaver specimens. A significative increase in the MCPFA value was found: Littler (P=0.01) and UTMP (P=0.01). The MCPFA with thumb loading was not significantly changed with the Littler (P=0.83) or UTMP (P=0.46) relative to pre-transection. All parameters were significantly improved, reflecting a return to normal values. There was no significant difference between the two reconstruction techniques. Based on the findings in this cadaver study, UTMP reconstruction appears to correct the radiologic features of lateral thumb instability. It is a simple technique that restores MCP stability without limiting MCP flexion. TYPE OF STUDY/LEVEL OF EVIDENCE: Therapeutic IV.

Computer-assisted 3D preoperative planning of corrective osteotomy for extra-articular distal radius malunion: A 16-patient case series.

The aim of this prospective study was to describe the surgical procedure and to report outcomes of computer-assisted 3D preoperative planning of corrective osteotomy for extra-articular distal radius malunions. Sixteen consecutive patients were enrolled. CT scans of both wrists were performed, and 3D bone surface models of the radii were created. Software was used to simulate the osteotomy and the reorientation of the distal radial articular surface. Patient-specific cutting and drilling guides for intraoperative guidance of the osteotomy as well as bone graft templates were also simulated. At a mean follow-up of 12 months (range 6-27) after surgery, pain was reduced from 3 to 0.3 at rest and 6.8 to 1.5 during effort according to a visual analog scale. The average wrist flexion-extension was 145° and pronation-supination was 155°. Grip strength was 91% of the contralateral side. All patients achieved primary bone union in a mean of 10 weeks (range, 7-18). Using our 3D analysis method, preoperative 3D values showed no significant difference with radiographic measurement. Moreover, there was no significant difference between the postoperative radiographic values in term of correction. This procedure provides satisfactory clinical and radiological results with minimal residual malalignment. LEVEL OF EVIDENCE: III.

Pedicled flap from the first dorsal branch of the proper palmar digital artery of the fingers: An anatomy study.

The pedicled flap from the first dorsal branch of the proper palmar digital artery (FBPPDA) of the fingers is an option for reconstructing digital skin defects. It has the advantage of being innervated by the dorsal branch of the proper palmar digital nerve (DBPPDN) associated with the artery. However, no studies on the anatomical variations of the neurovascular pedicle have been performed yet. The objective of our study was to evaluate the anatomical variations in the neurovascular pedicle, determine its relationships with other anatomical structures, describe the dissection technique for the FBPPDA and explore potential indications. We conducted an anatomical study with eight upper limbs from fresh adult cadavers. Twenty-six fingers (6 index, 6 middle, 8 ring, 8 little) were dissected after intra-arterial silicone injection. We found a pedicle composed of the FBPPDA and the DBPPDN in all fingers. The artery arises an average 19mm from the bifurcation of the common palmar digital artery. The DBPPDN's configuration relative to the FBPPDA varied; in the main variant - found in 58% of cases - the nerve was superficial and proximal position to the artery. After its origin, the pedicle ran on the superficial aspect of the extensor hood along an oblique path from proximal to distal and from palmar to dorsal. Its path ended with its penetration into the skin paddle of the flap just upstream the proximal interphalangeal (PIP) joint. The skin paddle corresponded to the functional skin unit represented by the dorsal surface of the middle phalanx and that of the PIP joint. Its average length was 33mm (26-40) and its average width was 21mm (15-30). The arc of rotation was sufficient to reach homodigital and heterodigital cutaneous defects. Based on our findings, this flap is a reliable and reproducible option for finger skin defects. The size of its paddle and its innervation make it an interesting alternative to conventional flaps.

Treatment of chronic scapholunate instability: Results with three-ligament tenodesis vs. scapholunate and intercarpal ligamentoplasty.

In this retrospective case control/comparison study, we compared the clinical and radiological outcomes in patients with chronic scapholunate dissociation treated with three-ligament tenodesis (3 LT) versus scapholunate and intercarpal ligamentoplasty (SLICL). Twenty patients with a mean age of 43 years were treated with the 3 LT procedure and 26 patients with a mean age of 44 years with the SLICL procedure. All patients had chronic reducible scapholunate dissociation without chondral lesions. The two groups of patients were operated on by senior surgeons, at the same facility, over two different time periods. All patients were evaluated (pain, motion, strength, function, X-rays) with a mean follow-up of 28 months (12-49) in the 3 LT group and 36 months (12-54) in the SLICL group. In the both groups, we found a significant improvement in pain levels, grip strength and functional scores (DASH and PRWE). The SLICL group had significantly less pain and greater grip strength than the 3 LT group. Patients in the SLICL group had a greater improvement in their DASH and PRWE Scores. The mean range of motion in flexion-extension was 82° (102° preoperative) in the 3 LT group and 113° (115° preoperative) in the SLICL group. In the 3 LT, there was no significant improvement in the mean static and dynamic scapholunate gaps (3.6 and 4.8 mm postoperatively versus 3.9 and 4.9 mm preoperatively), or the scapholunate angle (75° versus 72°). In the SLICL group, the mean static and dynamic gaps improved significantly (2.3 and 3.0 mm postoperatively versus 3.2 and 4.6 mm preoperatively), as did the scapholunate angle (62° versus 73°). In the 3 LT group, 4 patients developed osteoarthritis. In conclusion, the SLICL procedure for scapholunate ligament reconstruction led to better clinical and early radiological results than the 3 LT technique.

Distal interphalangeal joint arthrodesis using the X-Fuse® implant: A retrospective study of 54 fingers with 24 months' follow-up.

We report the clinical and radiographic results of distal interphalangeal (DIP) joint arthrodesis using the X-Fuse® implant with a mean follow-up of 24 months (6-54). Forty-one patients (33 women and 8 men) with a mean age of 65 years were operated on. DIP joint arthrodesis was performed on 54 fingers for advanced osteoarthritis resistant to medical treatment. Pain evaluated on a visual analog scale (/10) was reduced significantly, going from 5 to 0.47. Functional DASH and PRWE-Hand Scores (/100) were improved by 33 and 36 points, respectively. Four fingers (7.4%) were sensitive to cold. No cases of nail dystrophy were reported. The fusion rate was 89%. Of the six patients (11%) who suffered a non-union, there was one case of asymptomatic fracture of the implant, without reoperation, and one case of infection, which required revision surgery. The fusion position was stable at the review visit. The repeat surgery rate was 3.7%; both cases were for infection. In light of this study, the X-Fuse® implant is a viable alternative to traditional arthrodesis techniques (compression screws and pins), with a similar fusion rate. This implant appears to be very well tolerated by patients, with an absence of nail dystrophy and a reduction in the risk of infection.