Arthroscopically guided osteotomy for management of intra-articular distal radius malunions

Management of Extra-Articular and Intra-Articular Distal Radius Malunion

This article presents a comprehensive overview of managing extra-articular and intra-articular distal radius malunions (DRM), discussing the pathoanatomy, clinical, and radiologic evaluation, conservative treatment, and surgical strategies. Corrective osteotomy remains the primary surgical intervention for symptomatic DRM. Surgical planning should consider factors such as timing, approach, correction technique, implant, graft, and associated injuries. The correction of extra-articular malunion necessitates brachioradialis tenotomy, circumferential periosteum release, and intrafocal elevation with grafting to facilitate distal radius realignment following osteotomy. Computer-assisted planning with 3D-printed patient-specific instrumentation (PSI) could help execute extra-articular osteotomy with high precision. As for the management of intra-articular malunion, it may require wrist arthrotomy, arthroscopy, or PSI assistance for precise articular osteotomy and reduction of the joint surface. This review highlights the importance of early intervention, thorough preoperative planning, and appropriate surgical techniques to optimize outcomes and minimize complications. Future research should focus on large-scale randomized controlled trials to compare different surgical methods, particularly for intra-articular DRM.

Intra-Articular Corrective Osteotomy for Distal Radial Intra-Articular Malunion Using Patient-Matched Instruments: A Prospective, Multicenter, Open-Label, Single-Arm Trial

Background

Corrective osteotomy for intra-articular malunion is a challenging procedure. However, recent advancements, including patient-matched instruments created on the basis of preoperative computer simulation, enable accurate intra-articular correction. We hypothesized that intra-articular corrective osteotomy using patient-matched instruments for the treatment of distal radial intra-articular malunion would reduce intra-articular deformity and restore wrist function at 12 months of follow-up.

Methods

This prospective study included 12 patients with distal radial intra-articular malunion who underwent intra-articular corrective osteotomy external to the joint using patient-matched instruments. The primary end point was the maximum step-off on the articular surface of the distal radius, measured with use of computed tomography (CT), with an expected postoperative value of ≤1.5 mm. The secondary end points included the gap of the articular surface; range of motion; grip strength; pain evaluated using a visual analog scale (VAS); patient satisfaction; Disabilities of the Arm, Shoulder and Hand (DASH) score; and Patient-Rated Wrist Evaluation (PRWE) score. A mean postoperative step-off of ≤1.5 mm for the primary end point was assessed with use of the 1-sample t test. The secondary end points were assessed with use of the Dunnett multiple comparison test.

Results

The average step-off significantly improved from 3.75 ± 1.04 mm preoperatively to 0.51 ± 0.40 mm at the 52-week postoperative follow-up and was maintained within 1.5 mm. The average wrist and forearm range of motion, VAS score, grip strength, DASH score, and PRWE score significantly improved. Eleven patients were either very satisfied or satisfied with their outcomes.

Conclusions

The use of patient-matched instruments could contribute to improving postoperative outcomes of intra-articular corrective osteotomy procedures involving the distal radius.

Level of Evidence

Therapeutic Level IV. See Instructions for Authors for a complete description of levels of evidence.

Managing the Intra-articular Distal Radius Malunion

Intra-articular malunion of the distal radius represents a difficult clinical problem. While not all patients require treatment, corrective osteotomy may significantly improve motion, grip strength, and patient-reported outcome measures. Meticulous planning and technical precision are required with the possible need for multiple surgical approaches and both volar and dorsal implants. Arthroscopic assistance may be used to visualize the joint and articular reduction. Custom 3-dimensional planning guides are helpful in addressing complex multiplanar deformities. Regardless, intervention may not change the natural history of these injuries and post-traumatic arthritis is to be expected.

Arthroscopic Management of Distal Radius Fractures and Malunions

Articular congruity is the most important prognostic factor when dealing with a distal intra-articular radius fracture or the correction of intra-articular malunion. This article details our approach with tips and tricks for effectively managing these complex injuries with the aid of dry arthroscopy.

Intermediate-Term Outcome of 3-Dimensional Corrective Osteotomy for Malunited Distal Radius Fractures With a Mean Follow-Up of 6 Years

PURPOSE

Our study aimed to analyze the functional and radiological intermediate-term outcome of 3-dimensional-guided corrective osteotomies for malunited distal radius fractures and to evaluate the progression of osteoarthritis after this intervention.

METHODS

All patients with malunited distal radius fractures who underwent 3-dimensional-guided corrective osteotomies from October 2008 to January 2015 were included. Pre- and postoperative range of motion, grip strength, and postoperative patient-reported outcomes were assessed. Pre- and postoperative osteoarthritis grading was performed using conventional radiographs and the osteoarthritis grading system described by Knirk and Jupiter. Additionally, the evaluation of articular stepoff was performed using pre- and postoperative computed tomography.

RESULTS

Fifteen patients, with a mean follow-up of 6 years (range, 4.1-10.4 years), were included. According to rater 1, 8 cases had no postoperative osteoarthritis progression, 6 cases had progression of 1 grade, and 1 case had progression of 2 grades. According to rater 2, there was no progression in 11 cases, and there was progression of 1 grade in 2 cases and progression of 2 grades in 2 cases. Compared with before the surgery, the patients demonstrated a mean improvement of 14.8 kg (±12.6 kg) in grip strength after the surgery. At the last follow-up, the mean Patient-Rated Wrist Evaluation score was 11.8 (±12.0), the mean Disabilities of the Arm, Shoulder and Hand score was 11.1 (±11.4), and the mean residual pain score on the visual analog scale was 0.8 (±1.0).

CONCLUSIONS

The intermediate-term outcome of 3-dimensional-guided corrective osteotomies for distal radius intra-articular malunions showed excellent patient-reported outcomes and no clinically relevant progression of osteoarthritis.

TYPE OF STUDY/LEVEL OF EVIDENCE

Therapeutic IV.

Distal radius fractures

The management of distal radius fractures has evolved considerably in the last two decades. Techniques and hardware have improved so much that the surgeon can usually assure good results in these debilitating fractures. Yet no one method can be used for all injuries, as the personality of each fracture demands a customized approach. Furthermore, what works in one age group may not work in another. For this reason, every available treatment has its own space in our options. The need for surgeons to be well versed in all techniques is critical. We offer a concise update of important evolutionary and current treatment guidelines for this common fracture.

Accuracy and Early Clinical Outcome After 3-Dimensional Correction of Distal Radius Intra-Articular Malunions Using Patient-Specific Instruments

PURPOSE

To investigate the residual articular incongruity on computed tomography image data and the early clinical outcome of 3-dimensional planned and navigated intra-articular osteotomies of the distal radius.

METHODS

We conducted a retrospective analysis of intra-articular osteotomies executed between 2008 and 2016. We identified 37 patients (aged 26-73 years) and performed a combined intra-articular and extra-articular osteotomy on 20 patients. A preoperative 3-dimensional plan with the superimposed bone of the contralateral healthy side was performed in each case to analyze and execute the osteotomy by intraoperative navigation. The residual articular incongruity was assessed by quantification of the maximal stepoff in the coronal or sagittal computed tomography scans. Clinical outcome, including range of motion, grip strength, and return to work, was assessed after a minimum follow-up of 12 months and compared with preoperative measurements.

RESULTS

On average, the preoperative intra-articular stepoff was 2.5 mm (±0.6 mm; range, 1.4-4.2 mm) and was significantly reduced to 0.8 mm (±0.2 mm) after surgery. After surgery, 30 patients had a stepoff less than 1 mm; in 7, a stepoff of 1.1 to 1.4 mm was measured. After 1 year, 22 had no pain, 9 had slight pain during heavy work, and 5 had moderate pain with no improvement compared with their preoperative status, although wrist strength and range of motion improved in all 37 patients. One patient underwent a secondary radioscapholunate arthrodeses owing to persistent pain despite a congruent joint with a small residual intra-articular stepoff (0.6 mm).

CONCLUSIONS

Intra-articular osteotomies of the distal radius treated by 3-dimensional preoperative planning and patient-specific guides are an accurate technique to reduce articular incongruity to an average stepoff of 0.8 mm (range, 0.3-1.4 mm). The early clinical outcomes demonstrated overall reduction in pain and improvement of range of motion and grip strength in 36 of 37 patients.

TYPE OF STUDY/LEVEL OF EVIDENCE

Therapeutic IV.

Clinical and Epidemiological Features Among Patients with Wrist Arthroscopy Surgery: A Hospital-based Study in China

Propose

To analyze the clinical and epidemiological features of patients who underwent wrist arthroscopy procedures.

Methods

This is a cross‐sectional epidemiological study. The study included a cohort of patients who underwent wrist arthroscopy procedures in a national orthopaedic referral center from 1 February, 2014 to 1 February, 2019. The medical records, diagnosis, and every wrist arthroscopy procedure of all the patients were collected and reviewed. The epidemiological features, detail of the diagnoses, and the procedures of all the patients were systemically analyzed. All the patients were divided into two groups: trauma and non‐trauma conditions. The complexity of the wrist arthroscopy procedure was classified into simple procedures (exploration or debridement) and complex procedures (repair or reconstruction). χ² test was used to compare proportions between the procedures of different complexity and the two groups of patients.

Results

A total of 533 patients (332 males and 201 females) were included in this study. More than half (56%) of the patients were in the age group 21–40 and nearly two thirds (62%) of all the 533 patients were male. The diagnoses of all the patients could be classified into eight categories: (i) TFCC injury; (ii) ulnar impactions syndrome; (iii) carpal trauma (carpal bone fractures and/or carpal ligament injures); (iv) distal radius fractures; (v) carpal bone cyst or necrosis; (vi) ganglion cyst; (vii) wrist arthritis; and (viii) disorders of small joint of the hand. The most common conditions treated with wrist arthroscopy were TFCC injury (172 cases), followed by carpal trauma (125 cases) and ulnar impaction syndrome (84 cases). The simple arthroscopic procedures (exploration or debridement) account for 53% of all the procedures while complex reparative or reconstructive procedures account for 47%. There was a significant difference in the proportion between simple procedures and complex procedures in both trauma and non‐traumatic patients. Repair or reconstruction procedures were more frequently performed for wrist trauma patients, whereas exploration or debridement procedures were more frequently performed for non‐trauma patients.

Conclusions

The largest group of patients who underwent wrist arthroscopy surgery are those who complained of ulnar‐sided wrist pain and the commonly conducted wrist arthroscopy procedures have evolved from simple exploration/debridement to the more complex repair or reconstruction procedures in China.

Recent advances in the surgical treatment of malunions in hand and forearm using three-dimensional planning and patient-specific instruments

Malunions of the forearm and hand cause significant disability. Moreover, intraarticular deformities may contribute to early onset osteoarthritis. Such conditions require precise surgical correction in order to improve functional outcomes and prevent early or late complications. The purpose of this study was to describe the technical advantages of accurate anatomical reconstruction using 3D guided osteotomies and patient specific instruments (PSI) in multiple joints of the hand and forearm. Acquisition of three-dimensional (3D) datasets and surgical implementation of PSI was performed in a series of patients between December 2014 and July 2017. Patients had intra- or extra-articular malunions of the forearm, radiocarpal joint, trapeziometacarpal joint, or proximal interphalangeal joint. A previously described 3D surface model that incorporates CT data was used for segmentation (Mimics®, Materialise™, Belgium). For all the cases, CT scans of both forearms were acquired to use the contralateral uninjured side as the anatomic reconstruction template. Computer-assisted assessment of the deformity, the preoperative plan, and the design of PSI are described. Outcomes were determined by evaluating step-off correction, fusion, changes in range of motion (ROM) and grip strength. Six patients were included in the study; all achieved fusion. Improved clinical outcomes including pain reduction, better ROM and grip strength were obtained. Complete correction of intraarticular step-off was achieved in all cases with intraarticular malunions. 3D guided osteotomies are an established surgical treatment option for malunions of the hand and forearm. 3D analysis is a helpful diagnostic tool that provides detailed information about the underlying deformity. PSI can be developed and used for surgical correction with maximal accuracy for both intraarticular step-off and angular deformity.

Distal Radius Malunion

Malunion remains the most common complication of nonsurgical treatment of fractures of the distal radius and represents a common clinical entity. Symptomatic treatment often involves corrective osteotomy. Surgical correction is a challenging problem with unpredictable clinical outcomes. Prevention of malunion of a distal radius fracture is the best course of action. With maintenance of volar cortical contact and the use of volar fixed-angle devices, bone grafting may not be necessary in certain cases of malunion correction. New technologies such as 3-dimensional modeling and computer-generated osteotomy guides are likely to have a positive impact on the outcomes of surgical treatment.

Dry Wrist Arthroscopy for Radial-Sided Wrist Disorders

The development of wrist arthroscopy has been useful in diagnosis, prognosis, and treatment of both ligament and osseous injuries. As the treatment indications and techniques become more refined, this article explores the role of dry arthroscopy to treat radial-sided disorders of the wrist.

Corrective Intra-Articular Osteotomy Using a 3D-Printed Model and Induced Membrane Technique for AO/OTA C3 Distal Femur Fracture with Articular Malunion and Metaphyseal Nonunion

Comminuted distal femur fracture is a challenging injury, and care must be taken to reduce the articular fragment and acquire the sufficient stability for the metaphyseal comminution. We report the case of a AO/OTA C3-type distal femur fracture with articular malunion and metaphyseal nonunion. Articular malunion was treated with corrective osteotomy using a 3D-printed model for planning, and metaphyseal nonunion was treated with an induced membrane technique. Conclusion. Two major complications in the comminuted periarticular fracture can be addressed by an osteotomy and induced membrane technique. A 3D-printed model is a useful tool to evaluate the morphology of the malunited articular surface.

Intra-Articular Osteotomy of the Distal Radius with the Use of Inexpensive In-House 3D Printed Surgical Guides and Arthroscopy: A Case Report

CASE

An 18-year-old man complained about persistent wrist pain and functional impairment due to intra-articular malunion, 1 year after volar plating of a distal radius fracture. We designed and produced patient-specific surgical guides (PSSGs) in-house with a benchtop three-dimensional printer to perform an arthroscopy-assisted intra-articular osteotomy of the radial column without dorsal arthrotomy. The procedure was performed without complications. After 1 year, there was no osteoarthritis and the patient's wrist function was practically normalized.

CONCLUSIONS

Virtual surgical planning, design, and production of PSSGs were feasible without consultation of an external medical engineering company and without dorsal arthrotomy.

Best Approaches in Distal Radius Fracture Malunions

PURPOSE OF REVIEW

Malunion remains a common complication in the treatment of distal radius fractures. The purpose of this review was to discuss the various approaches in planning and surgical management for extra- and intra-articular distal radius malunions.

RECENT FINDINGS

Several recent studies have reported good results with surgical correction of distal radius malunions utilizing a number of preoperative planning methods and surgical approaches. Three-dimensional models and custom cutting guides have recently become more popular, but their benefit in comparison to other methods remains unclear. Regardless of preoperative planning method or surgical approach, good results can be achieved with correction of distal radius malunion with careful attention to patient selection, indications, and surgical technique.

Effectiveness of an Arthroscopic Technique to Correct Supination Losses of 90° or More

PURPOSE

To present a new arthroscopic method for treating supination losses.

METHODS

Six patients (15-71 y) were eligible for this study. All had a history of trauma to the wrist more than 6 months previously. Five of them had sustained a distal radius fracture: 3 had been treated with a volar plate (1 of them for an extra-articular malunion), 1 with an external fixator and K-wires, and 1 had been treated in a cast. One of these patients underwent a further operation for correcting an intra-articular malunion. The last patient underwent an open reduction of a transscaphoid perilunate dislocation. During a standard radiocarpal arthroscopy, a curved periosteal elevator was inserted through the 6R portal into the volar-radial corner of the triangular fibrocartilage complex and advanced proximally gliding on the anterior ulnar head surface. The volar capsule was then distended with the periosteal elevator and by means of gentle sweeping motion adherences between them, the volar capsule and the ulnar head were freed. Finally, the arthroscopic release was combined with a gentle passive supination force applied by the surgeon. Full supination was maintained in an orthosis for 2 to 3 days. Afterward, regular physical therapy was instituted. Concomitant surgery, arthroscopic or open, was performed in all to treat associated conditions.

RESULTS

Full supination (90°) was achieved in all intraoperatively. At a mean follow-up of 3.3 years, mean supination was 76° in the latest follow-up (range, 50° to 90°). Mean improvement in supination was 80° (range, 50° to 100°). No distal radioulnar instability or other complications were noted.

CONCLUSIONS

The method presented proved effective in severe forms of supination deficits.

TYPE OF STUDY/LEVEL OF EVIDENCE

Therapeutic V.

Arthroscopic Management of Intra-articular Malunion in Fractures of the Distal Radius

Treatment of intra-articular malunion of the distal radius has evolved over the past 20 years, from open treatment to wet then dry arthroscopic techniques that provide excellent results with less morbidity than open approaches. Dry wrist arthroscopy provides a well-visualized surgical space in treating intra-articular malunion and results in less edema than wet techniques. The best results are attained in the first 3 months after injury. Alternative methods for avoiding total wrist arthrodesis in those who present later have been developed. The dry arthroscopic "inside-out" osteotomy technique for intra-articular malunions should be considered in patients with this condition.

Wrist Arthroscopy for Athletic Injuries

Management of hand and wrist injuries for athletes often places emphasis on an expeditious return to sport. Arthroscopic techniques have the advantage of directly visualizing joint derangements and correcting them via a minimally invasive approach. This article discusses the evaluation and management of common wrist injuries treated with arthroscopy in athletes, including scapholunate and lunotriquetral injury, triangular fibrocartilage complex tears, hamatolunate impingement, and arthroscopic-assisted reduction of wrist fractures.

Vascularized graft from the metatarsal base for reconstructing major osteochondral distal radius defects

PURPOSE

To present our experience of reconstructing distal radius articular defects with a vascularized osteochondral graft from the metatarsal base and to present the mid-term outcomes.

METHODS

Seven patients (average age, 36 y; range, 26-55 y) who had reconstruction of major defects of the articular surface of the radius are presented. In 5, the lunate facet and sigmoid notch were reconstructed; in 1, an isolated defect on the surface of the lunate facet was reconstructed; and in 1, the scaphoid facet was reconstructed. In 6, the base of the third metatarsal was transferred, and in 1, the base of the second was transferred.

RESULTS

All flaps survived without complications. At the latest follow-up (range, 20 mo to 8 y), the flexion-extension arc improved an average of 50°, and the pain on a visual analog scale decreased from 8 to 1 on average. Disabilities of the Arm, Shoulder, and Hand score improved from 54 to 11 on average. One patient did not improve. No major complaints related to the donor site were mentioned (average American Orthopedic Foot and Ankle Society score of 96/100).

CONCLUSIONS

Our mid-term results are promising; however, the decision-making process and the operation are complex. The operation is not indicated when the carpals are devoid of cartilage or when the defect involves the whole radius surface.

Arthroscopic resection arthroplasty for malunited intra-articular distal radius fractures

PURPOSE

Cartilage damage of the carpals is a contraindication for corrective osteotomy of the malunited intra-articular distal radius fracture and typically is treated in the symptomatic patient with a salvage procedure. Here, we present our experience and early results with arthroscopic resection arthroplasty of the radiocarpal joint.

METHODS

We treated 10 patients (age, 17-68 y; average, 53 y) who had intra-articular malunion of the distal radius with mirror erosion on the carpals. The original fracture occurred 4 to 36 months (average, 9 mo) before our intervention. We performed arthroscopic arthrolysis and resected the offending portion of the radial malunited fragment, eliminating the stepoff and creating a smoother joint surface. Range of motion was started immediately after the operation, except in 2 patients.

RESULTS

The locations of the malunions were evenly distributed between the scaphoid fossa, the lunate fossa, or both. Stepoffs varied from 2 to 6 mm. We resected up to 60% of the entire radial articular surface to obtain a smooth surface (average, 28%; range, 20% to 60%). All patients reported immediate relief of pain and improvement in motion (particularly extension). At the latest follow-up (average, 28 mo; range, 13-42 mo), average extension improved from 24° to 54°, average grip strength improved from 47% to 89% of the contralateral wrist, average Disabilities of the Arm, Shoulder, and Hand score improved from 74 to 18, and average Patient-Rated Wrist Hand Evaluation score improved from 79 to 15.

CONCLUSIONS

The aim of the operation was to relieve patients' pain by providing a smooth, although fibrocartilaginous, surface for the carpus to glide on the radius. The follow-up was short and the results may be short-lived. However, for the younger patient, it may provide a temporary alternative to partial wrist arthrodesis with minimal morbidity, and for the less demanding patients, it may be a definitive procedure.

Early experience with (dry) arthroscopic 4-corner arthrodesis: from a 4-hour operation to a tourniquet time

PURPOSE

Scaphoidectomy and 4-corner arthrodesis (4CA) is an effective procedure for treating several degenerative conditions of the wrist. Recently, the arthroscopic approach to this operation was described. Although it is conceptually appealing, certain aspects make its application difficult. We present our technique for dry arthroscopic scaphoidectomy and 4CA, which reduces the operative time to less than 2 hours.

METHODS

Four consecutive patients underwent scaphoidectomy and 4CA. In each case, we performed the operation with a dry arthroscopic technique using cannulated screws for rigid fixation. We performed bone grafting from the distal radius in 2 patients and from the scaphoid itself in the other two. The relevant operative details are the use of a scapholunate portal, the resection of the scaphoid with a pituitary rongeur, and the placement of bone graft in a dry arthroscopic environment. Range of motion exercises are started 2 to 3 weeks after the operation.

RESULTS

The first operation took 4 hours. The last 2 were completed in 1 hour 45 minutes and 1 hour 55 minutes, respectively. No complications occurred. No operations were converted to an open procedure.

CONCLUSIONS

Although the operation has a steep learning curve, it is conceptually appealing. It is too early to prove that the arthroscopic procedure has better results than the open 4CA; nevertheless, in our opinion it represents the future of wrist surgery.

Current innovations in wrist arthroscopy

It has become clear that the stability of the scapholunate joint does not depend wholly on the scapholunate interosseous ligament, but rather on both primary and secondary stabilizers, which form a scapholunate ligament complex. Each case of scapholunate instability is unique and should be treated with tissue-specific repairs, which may partly explain why one procedure cannot successfully restore joint stability in every case. Wrist arthroscopy has a pivotal role in both the assessment and treatment of the scapholunate ligament complex derangements. Tears of the foveal attachment of the triangular fibrocartilaginous complex can be an underdiagnosed cause of distal radioulnar joint instability, because the foveal fibers cannot be visualized using the standard radiocarpal arthroscopy portals. Distal radioulnar joint arthroscopy allows for direct visualization and assessment of these fibers, which in turn has spawned a number of open and arthroscopic repair methods. Wrist arthroscopy has gained wider acceptance as a method to fine-tune articular reduction during open and percutaneous fixation of distal radius fractures, and simplifies intra-articular osteotomies for malunion. It can facilitate percutaneous bone grafting of scaphoid nonunions and has a role in the diagnosis and treatment of associated soft tissue lesions. These and other recent developments will be discussed in the following article.

Intra-articular corrective osteotomy for malunited Hoffa fracture: A case report

Hoffa fracture, an isolated coronal plane fracture of the posterior aspect of the femoral condyle, is known as an unstable, intra-articular fracture, and therefore, operative treatment is recommended. However, insufficient open reduction or failure of fixation may lead to malunion. We performed intra-articular corrective osteotomy for a malunited Hoffa fracture in a 31-year-old man and obtained good functional and radiographic results. This report suggests that intra-articular corrective osteotomy for malunited Hoffa fracture offers a good outcome and should be considered as salvage treatment.

Radial styloid fractures

Radial styloid fractures can occur in isolation or in association with other injuries, including complex intra-articular distal radius fractures, carpal fractures, carpal dislocations, and radiocarpal dislocations. The anatomy surrounding the radial styloid is complex, and complications related to surgical approach, treatments, and symptomatic hardware can occur. Operative treatments vary according to the injury pattern present, and pattern recognition is the key to optimizing treatment of these injuries. Outcomes are related to the precision of the reconstruction as well as the magnitude of the injury; better results are associated with lower-energy patterns.

The biomechanical effects of a deepened articular cavity during dynamic motion of the wrist joint

BACKGROUND

A deepened articular cavity of the distal radius due to a metaphyseal comminution zone is associated with early osteoarthritis and reduced joint motion. As this deformity has not been investigated biomechanically, the purpose of this study was to evaluate the effects of a deepened articular cavity on contact biomechanics and motion range in a dynamic biomechanical setting.

METHODS

Six fresh frozen cadaver forearms were tested in a force controlled test bench during dynamic flexion and extension and intact mean contact pressure and contact area as well as range of motion were evaluated. Malunion was then simulated and intraarticular as well as motion data were obtained. Intact and malunion data were compared for the scaphoid and lunate facet and the total radial joint surface.

FINDINGS

Due to malunion simulation, cavity depth increased significantly. Motion decreased significantly to 54-69% when compared to the intact state. Malunion simulation led to a significant decrease of contact area in maximum extension for all locations (by ~50%). In maximum flexion and neutral position, contact area decrease was significant for the scaphoid fossa (by 51-54%) and the total radial joint surface (by 47-50%). Contact pressure showed a significant increase in maximum extension in the scaphoid fossa (by 129%).

INTERPRETATION

Already a small cavity increase led to significant alterations in contact biomechanics of the radiocarpal joint and to a significant range of motion decrease. This could be the biomechanical cause for degenerative changes after the investigated type of malunion. We think that restoration of the normal distal radius shape can minimize osteoarthritis risk post trauma and improve radiocarpal motion.

Dry arthroscopy and its applications

Wrist arthroscopy can be performed without infusing fluid, as simple traction suffices to maintain the working space. The lack of tissue infiltration by fluid keeps soft tissues in pristine condition if open surgery is needed after the arthroscopic exploration. The dry technique makes fluid distension irrelevant, thus opening new possibilities by combining arthroscopy with moderate-sized incisions. Although any modification of a technique with which one is familiar can be regarded with major reticence, the advantages of the dry technique merit its use. Accomplished wrist arthroscopists will have minimal problems swapping from the wet to the dry and vice versa.