Carpal Arthrodesis Research Articles

Carpal bone replacement using personalized 3D printed tantalum prosthesis

Objective:Scaphoid and lunate fractures have a relatively high incidence rate. Traditional carpectomy and carpal arthrodesis in the treatment of carpal osteonecrosis will lead to many complications. Three-dimensional (3D) printed tantalum has good biocompatibility and can be designed to match the patient’s personalized anatomical carpal structure. This study aims to investigate carpal function and prosthesis-related conditions after carpal bone replacement using 3D printed tantalum prostheses.Methods:From July 2020 to January 2022 at our center, seven patients with osteonecrosis of the carpus received carpal bone replacement using 3D printed tantalum prosthesis. The Disability of the Arm, Shoulder and Hand (DASH) score and patient satisfaction, as well as the Mayo Wrist Scores (Cooney method, modified Green, and O’Brien wrist score), were used to evaluate the preoperative and postoperative wrist function of patients. The Visual Analog Scale (VAS) pain scores were also recorded before and after surgery. The angles of flexion, dorsiflexion, ulnar deviation, and radial deviation were measured using an arthrometer. The grip strength and pinch strength of the operated hand after carpal bone replacement and the contralateral healthy carpus were measured using a dynamometer. Radiographs were taken to confirm the condition and complications of the tantalum prosthesis.Results:All seven patients were followed for 19.6 ± 2.7 months. At the last follow-up, the grip strength of the operated wrist joint after carpal bone replacement was 33.4 ± 2.3 kg, the pinch strength was 8.9 ± 0.7 kg, the flexion was 54.6° ± 0.8°, the dorsiflexion was 54.7° ± 1.7°, the ulnar deviation was 34.6° ± 1.9°, and the radial deviation was 25.9° ± 0.8°, all of which showed no statistically significant difference with the contralateral healthy carpus (p> 0.05). There were significant differences in the VAS, DASH, and MAYO scores between the preoperative and the last follow-up (p< 0.01). Patients had reduced postoperative pain and improved wrist function and range of motion (ROM), and the tantalum prostheses were stable.Conclusion:The 3D printed tantalum brings us new hope, not only for hip or knee replacement, but also for joint replacement of other complex anatomical structures, and patients with other irregular bone defects such as bone tumors and deformity, which could realize personalized treatment and precise medicine.

Pan‐carpal arthrodesis as a treatment for distal radial fracture in a pony

SummaryComplete, displaced radial fractures carry a poor prognosis in adult horses. In foals and ponies, fracture repair may have a good outcome following internal fixation. Distal radial fractures are difficult to stabilise due to limited bony purchase. Therefore, carpal arthrodesis may provide a viable option for salvaging the horse. In this report, we describe pan‐carpal arthrodesis as a treatment for distal radial fracture in an adult pony. A 12‐year‐old pony, 180 kg bodyweight, was presented due to left front non‐weight bearing lameness. Diagnosis of a closed, comminuted, displaced distal radial fracture, with antebrachiocarpal joint involvement, was made radiographically. The fracture was repaired and pan‐carpal arthrodesis was performed. Recovery was uneventful. The implants were gradually removed, in a minimally invasive standing procedure, due to surgical site infection. Two years following surgery, the horse is sound at a walk and trots freely with flexion of the affected carpus. Radiographs revealed healing of the fracture and failure of the arthrodesis. In essence, unintentionally, we performed temporary trans‐articular stabilisation by repairing a distal radial comminuted fracture, while preserving partial carpal range of motion. This technique, of temporary trans‐articular stabilisation, could be applied intentionally on other distal or proximal long bone fractures in horses.

Advanced Arthritis of the Carpus: Preoperative Planning Practices of 337 Hand Surgeons.

Background Surgical procedure selection for carpal arthritis depends on which articular surfaces are affected, but there is no consensus on how to preoperatively evaluate cartilage surfaces. Despite advances in cross-sectional imaging, the utility of advanced imaging for preoperative decision-making has not been well established. Objectives Our objective was to assess if there is an added value to presurgical advanced imaging or diagnostic procedures in planning for carpal arthrodesis or carpectomy and to determine what imaging or diagnostic procedures influence surgical treatment options. Methods A seven-question survey was sent to 2,400 hand surgeons. Questions assessed which articular surfaces surgeons consider important for decision-making, which imaging modalities surgeons employ, and how often surgeons utilize diagnostic arthroscopy before performing carpectomy or arthrodesis procedures. Results A total of 337 (14%) surveys were analyzed. The capitolunate articulation (alone or in combination) was most frequently reported to impact surgical decision-making (48.1%). Most surgeons (86.6%) reported that standard plain radiographs are usually sufficient. Few surgeons reported always obtaining magnetic resonance imaging (MRI) or computed tomography (CT), with 44.2% of surgeons believing that MRI is never useful and 38.4% believing that CT is never useful. Most surgeons (68.2%) reported that they never perform wrist arthroscopy as part of their decision-making process. Conclusions This study provides information on the decision-making process in the surgical management of carpal arthritis. Given advances in cross-sectional imaging, further studies are needed to determine the utility of MRI and CT for the planning of surgical procedures in the treatment of arthritis of the carpus. Level of Evidence Level 4.

Implant removal rate after partial carpal arthrodesis in dogs: A retrospective analysis of 22 cases.

The purpose of this study is to determine the rate of implant removal after partial carpal arthrodesis and to investigate factors associated with implant removal. Case records of 22 dogs that underwent partial carpal arthrodesis at two private veterinary referral hospitals were reviewed. Details retrieved were body weight at time of surgery, sex, neuter status, breed, age, cause of carpal hyperextension injury, joint(s) involved in carpal hyperextension injury, laterality, type of implant, administration of post-operative antibiotics, post-operative outcome and indication for implant removal. Association between these factors and implant removal was evaluated. Of 22 partial carpal arthrodesis, 12 (55%) had implant removal due to persistent lameness and 9/12 (75%) returned to full and acceptable function after implant removal. Indications for implant removal were implant interference (8), infection (4), and migration (1). When comparing type of implant, there was a significant difference when observing implant removal rates (p = 0.04). All 5 dogs with pins and wires (100%) required implant removal. Of 17 dogs with a plate, 7 (41.2%) required implant removal. Implant removal was performed on average 114 days post-operative. Implant removal after partial carpal arthrodesis was frequent and was commonly indicated due to pin and wire fixation or plate implant interference. This study may impact how we prepare clients for potential post-operative complications and implant removal when recommending partial carpal arthrodesis.

Combined radial wedge and shortening osteotomy versus scaphocapitate arthrodesis in advanced Kienböck’s disease

Although various surgical techniques have been reported for the treatment of advanced Kienböck's disease (Lichtman stage IIIB and above), the ap- propriate operative treatment is still being debated. This study compared the clinical and radiological outcomes of combined radial wedge and shortening osteotomy (CRWSO) and scaphocapitate arthrodesis (SCA) in the treatment of advanced Kienböck's disease (above type IIIB) with a minimum of 3 years of follow-up. We analyzed the data from 16 and 13 patients who underwent CRWSO and SCA, respectively. The average follow-up period was 48.6±12.8 months. Clinical outcomes were evaluated using the flexion-extension arc, grip strength, Disabilities of the Arm, Shoulder, and Hand Questionnaire (DASH), and Visual Analogue Scale (VAS) for pain. The following radiological parameters were measured: ulnar variance (UV), carpal height ratio (CHR), radioscaphoid angle (RSA), and Stahl index (SI). Osteoarthritic changes in the radiocarpal and midcarpal joints were evaluated using computed tomography (CT). Clinically, both groups showed significant improvements in the grip strength, DASH, and VAS at final follow-up. However, regarding the flexion-extension arc, the CRWSO group showed a significant improvement, while the SCA group did not. Radiologically, compared to the preoperative values, the CHR results improved at final follow-up in the CRWSO and SCA groups. There was no statistically significant difference in the degree of CHR correction between the 2 groups. By the final follow-up visit, none of the patients in either group had progressed from Lichtman stage IIIB to stage IV. Considering restoration of wrist joint range of motion, CRWSO may be a good alternative for limited carpal arthrodesis for advanced Kienböck's disease.

Retrospective Comparison of Titanium Hybrid Locking Plate with Stainless Steel Hybrid Dynamic Compression Plate for Pancarpal Arthrodesis: 23 Dogs

The aim of this study was to evaluate outcomes and complications of dogs that had pancarpal arthrodesis (PCA) using a titanium hybrid advanced locking plate system (ALPS) and stainless steel hybrid dynamic compression plate (HDCP). Retrospective observational study. Medical records (2007-2020) were reviewed for cases that had PCA performed using ALPS or HDCP. Implant characteristics including metacarpal coverage (MCov), metacarpal width occupied by screw diameter percentage and carpal arthrodesis angle (CAA), complications and outcomes were recorded. Pancarpal arthrodesis was performed with ALPS on 15 limbs from 12 dogs, and HDCP on 14 limbs from 11dogs. Median follow-up time was 1,157 days (range: 62-1,902 days) for ALPS group and 340 days (range: 43-1,465 days) for HDCP. Median MCov for ALPS group was 74% (range: 60-87.5%) compared with 56.5% (range: 49.7-91.3%) for HDCP (p = 0.001). There was no difference in CAA and metacarpal width to screw diameter percentage between ALPS and HDCP group. Major and minor complications and surgical site infection rates were not statistically different between the two groups. Plate fracture occurred in 2/15 ALPS PCA and screw loosening occurred in 4/14 HDCP PCA. Full function was achieved in 8/12 AND 8/11 OF ALPS AND HDCP: cases, respectively, which was not statistically different (p = 0.76). The use of ALPS offers comparable performance to HDCP for PCA.

Augmentation of Carpal Arthrodesis Using Mesenchymal Stem Cells Derived Microvesicles and Cancellous Bone Graft in Dogs

Augmentation of Carpal Arthrodesis Using Mesenchymal Stem Cells Derived Microvesicles and Cancellous Bone Graft in Dogs

Surgical site infection associated with equine orthopedic internal fixation: 155 cases (2008-2016).

To determine the prevalence of surgical site infection (SSI) after internal fixation and to identify risk factors for SSI and nonsurvival. Retrospective study. One hundred fifty-five horses with long bone fractures or arthrodesis treated by internal fixation at 1 hospital between 2008-2016. Signalment, diagnosis, surgical repair, surgeon, surgical time, antimicrobial use, SSI onset, bacterial identification, and adjunct treatments were recorded. Perioperative variables were analyzed to identify risk factors associated with outcomes. Surgical-site infection was reported in 22 of 155 (14.2%) horses, which is lower than what has been previously reported (P = .003). Horses with fetlock arthrodesis or ulnar fracture were more likely to develop SSI. Local prophylactic antimicrobial therapy was associated with an increased risk of SSI. Horses with SSI were 12 times (P < .0001) less likely to survive to discharge than horses without SSI. Horses with a fetlock or carpal arthrodesis or those with radial/humeral/femoral fractures were less likely to survive. No association was identified between open fractures, open reduction and internal fixation, or surgical times and SSI. The prevalence of SSI in this population was lower than what has been previously reported. Horses with fetlock or carpal arthrodesis or radial/humeral/femoral fractures were at increased risk for SSI and/or nonsurvival to discharge. A protective role of local antimicrobial therapy for SSI could not be established. The impact of SSI on outcomes of cases of equine internal fixation remains substantial. Identification of cases at higher risk of SSI should influence surgical technique, postoperative management, and early intervention when SSI is suspected. Additional investigation is warranted regarding local antimicrobial therapy.

Fractures of the carpus

The carpus is a complex joint, consisting of seven bones arranged in two rows, with multiple ligamentous supports originating from, inserting on and connecting the bones. Individual fractures of the bones of the carpus are rare, and, due to the small size of some bones, repair may not be possible. For the larger carpal bones, repair is indicated where fragments are large enough and especially if the fracture is articular. Several methods of repair are suitable, although compression of the fragments using lag screws or headless, self-compressing cannulated screws is often ideal. Where the fragments are too small, removal may be advised and external coaptation is often used in conjunction. For non-repairable fractures of the articular surfaces, and other carpal injuries precluding primary repair, partial carpal arthrodesis or pancarpal arthrodesis may be considered as salvage procedures. The prognosis for recovery from carpal fractures depends on the type of injury, the bone affected, the method of repair and the desired performance of the patient.

The Advantages of Type III Scaphoid Nonunion Advanced Collapse (SNAC) Treatment With Partial Carpal Arthrodesis in the Dominant Hand: Results of 5-year Follow-up.

Introduction:The SNAC wrist (Scaphoid nonunion advanced collapse) is one of the complications following scaphoid fractures treated conservatively and one of the causes of wrist arthritis that the hand surgeon has to face most frequently. In these cases surgical management is usually warranted.Materials and Methods:In the set time frame of 6 years we treated 15 SNAC wrist cases. On average patients underwent surgery five years after the trauma. All patients were treated via dorsal incision with partial carpal arthrodesis and total scaphoidectomy, associated with denervation of the posterior interosseous nerves. A plaster cast was applied to all patients for 3 weeks postoperatively. In the preoperative stage, X-rays of the healthy contralateral limb were taken for the measurement of the normal radiocarpal joint space. Clinical and radiographic follow-ups were conducted at 1,3, 6 and 12 months from the trauma; then every 12 months. Criteria for the evaluation of patients: visual analog pain scale (VAS), average time of radiographic fusion of wrist bones, Active Range of Wrist Motion (WAROM), subjective Mayo Wrist Score (MWS) and The Short Form ( 36) Health Survey (SF-36), return to the main tasks and complications. The evaluation endpoint was set at 60 months. Average time of surgery: 48.3 minutes. Average time of arthrodesis consolidation: 67.8 days. The VAS and WAROM showed a gradual improvement in seriated controls, returning to values almost identical to pre-trauma at a 5-year follow-up. By this time, the MWS and SF-36 scores were similar to pre-trauma. On average, the return to pre-injury daily activities occurred in 12.5 months after surgery. There were no complications.Conclusions:The partial carpal arthrodesis is a safe and effective procedure for the treatment of SNAC wrist cases. Our results show a progressive and significant improvement in ROM, VAS and great satisfaction from the patient.

Limb shortening as a strategy for limb sparing treatment of appendicular osteosarcoma of the distal radius in a dog.

To develop and report a novel limb sparing technique for the distal radius in a dog. Case report. A 14-year-old, female spayed Labrador Retriever with an osteosarcoma of the right distal radius and a pathological fracture. A previous mast cell tumor had been treated 5 years prior to presentation with marginal excision and a full-course radiation over the right metacarpal bones. The dog had received 2 doses of palliative radiation just prior to presentation. A standard resection of the distal radius was used as a strategy to salvage the limb. Instead of replacing the 6-cm bone defect with an endoprosthesis, the limb was acutely shortened and a carpal arthrodesis plate was applied. Postoperative function was good and limb shortening was well-tolerated. Radiographic evidence of early bone healing was noted at the osteotomy site. The dog experienced 3 postoperative complications: a focal area of skin necrosis managed successfully via surgical revision; infection resolving after long-term antibiotherapy; and a fracture of the third metacarpal bone through a screw hole, managed via screw removal and a custom external prosthesis. The patient was euthanatized due to presumptive chemotherapy complications 127 days after the procedure. Limb shortening limb salvage is technically feasible and can result in excellent limb use postoperatively, in spite of a significant loss in limb length.

Lunate fossa arthroplastie de résection pour maladie ancienne Kienbock

Kienbock disease is relatively rare condition that has usually good prognosis with or without treatment. Sometimes (especially in neglected cases), we faced with patients with obvious degenerative changes in lunate fossa and pain. There are different options for this problem from resection of the lunate to different types of limited and complete wrist fusion. We started to treat these patients with a simple resection arthroplasty of lunate fossa and evaluated their final results in a 12 to 39 months follow up. Six patient: five male and one female, with wrist pain and known diagnosis of previous Kienbock disease underwent lunate fossa resection arthroplasty. Inclusion criteria were disabling pain resisted to medication and splinting, plain radiography showed degenerative changes in lunate fossa without generalized osteoarthritis. The technique was a simple resection of two to three millimeter thickness of the degenerative lunate fossa with a cutting burr via trans-4 portal as working portal. The patients’ age was from 36 to 45 years. Two patients had previous radial shortening four and five years before index surgery, three patients have had refused surgical treatment and the pain had been increased before index surgery, and one patient had come with advanced stage of the disease without previous history of the diagnosis and treatment. Total mean arc of range of motion f the wrist increased from 42 to 58 degrees. Mean VAS score decreased from 6.3 to 2.1. Quick DASH score decreased from 45 to 22. Four patients satisfied from decreasing wrist pain, one patient showed no pain relief and one patient underwent total wrist arthrodesis. The rational of lunate fossa resection arthroplasty are: – scaphoid fossa spares even in late stages of Kienbock disease; – well known good results of arthroscopic resection arthroplasty at 1st CMC rhizarthrosis which has the same rdiologic findings; – acceptable indication of radius styloidectomy in isolated degenerative changes of this articular surface. Reasons against this technique are: – the majority of the force in radiocarpal joint crosses from lunate fossa; – the differences between simple debridement and complete resection is hard to judged; – degenerative changes could be accelerates with changing the carpal biomechanique after this procedure. We suggest this simple technique in patients with neglected or failed previous treated Kienbock disease with degenerative changes in lunate fossa and sparing other perilunate articular surfaces before trying for any type of carpal arthrodesis.

Carpal arthrodesis using a minimally invasive approach and locking compression plates: Three cases

SummaryThree horses with carpal instability due to comminuted second carpal bone fractures (Cases 1 and 3), fracture of the head of the second metacarpal bone (Case 1) or comminuted fractures of the fourth carpal bone, ulnar and intermediate carpal bones (Case 2) were treated by minimally invasive approach for partial (Cases 1 and 3) or pancarpal (Case 2) joint arthrodesis, using locking compression plates. The joint cartilage was removed by either an arthroscopic approach (middle carpal joint and antebrachiocarpal joint) or a percutaneous drilling technique (carpometacarpal joint). Two or 3 locking compression plates were contoured to the dorsolateral, dorsomedial and dorsoaxial aspects of the carpal joints using a custom‐made tunnelling tool and a minimally invasive tunnelling technique, and the screws were positioned through stab incisions. All cases recovered well, were lame free at the walk, were able to trot and gallop and could be used for leisure and pasture activities (partial carpal arthrodesis) and breeding (pancarpal arthrodesis). Post‐operative x‐rays showed progressive joint fusion after 12 months (Case 1), 5 months (Case 2) and 10 months (Case 3). Case 2 with a pancarpal arthrodesis showed a mechanical lameness at the walk due to the inability to flex the carpus. Carpal flexion after carpometacarpal and middle carpal arthrodesis in Case 1 was calculated to be 42.6° and 44° in Case 3.

Load distribution on the radio-carpal joint for carpal arthrodesis

Background and objectiveCarpal fusions are useful for treating specific carpal disorders, maximizing postoperative wrist motion, hand strength, reducing pain and instability of the joint. The surgeon selects the appropriate treatment by considering the degree of stability, the chronicity of the injury, functional demands of the patient and former patient's outcomes as well. However there are not many studies regarding the load distribution provided by the treatment. So, the purpose of this study is to analyze the load distribution through the wrist joint with an arthrodesis treatment and compare the results with a normal wrist. MethodTo this end the rigid body spring model (RBSM) method was used on a three-dimensional model of the wrist joint. The cartilage and ligaments were simulated as springs acting under compression and tension, respectively, while the bones were considered as rigid bodies. To simulate the arthrodesis, the fused bones were considered as a single rigid body. ResultsThe changes on the load distribution for each arthrodesis agree with the treatment objective, reducing load transmission through a specific articular surface. For example, for SLAC/SNAC II most of the treatments reduced the load transmitted through the radioscaphoid fossae, almost by 8%. However, the capitolunate (CL) arthrodesis was the treatment that managed to keep the load transmitted through the radiolunate joint closer to normal conditions. Also, in treatments where the scaphoid was excised (3-corner, 4-corner and capitolunate arthrodesis), the joint surface between the lunate surface compensates by doubling the transmitted force to the radius. ConclusionsThe common arthrodesis for treating SLAC/SNAC II-III, reduces, in fact, the load on the radioscaphoid joint. Alternative treatments that reduce load distribution on the radiocarpal joint should be three corner and capitolunate arthrodesis for treating SLAC/SNAC-II; and for SLAC/SNAC-III four corners with scaphoid excision. On Kienbock's disease. Scaphocapitate (SC) arthrodesis is more effective on reducing the load transmission through the radiolunate and ulnolunate joints. All arthrodesis treatment should consider changes on the load transmission, and also bones’ fusion rates and pain reduction on patient's outcomes.

Long-term follow-up of working dogs in New Zealand following pancarpal arthrodesis using dorsal hybrid plating

AIM: To determine the long-term prognosis for working dogs in New Zealand following pancarpal arthrodesis (PCA) utilising a dorsal hybrid plate.METHODS: Owners of 14 dogs who had a PCA performed as part of a previous study conducted at two small animal veterinary surgical hospitals were contacted via phone and asked to participate in a short survey.RESULTS: A phone survey was completed for seven dogs. Five of the seven dogs had returned to full work, one dog had a moderate persistent lameness that prevented returning to normal work and the remaining dog did not return to normal work for reasons unrelated to the study. Removal of the implants was required in four of seven cases at a median interval of 2 (min 0.5, max 2) years following surgery. One dog had no gait abnormality, but developed an occasional mild lameness after jumping, one dog had a constant gait abnormality with a moderate, persistent lameness, and the remaining five dogs had a constant gait abnormality with a mild, intermittent lameness. All owners contacted were very satisfied with the procedure.CONCLUSIONS: Working dogs undergoing a standardised surgical procedure for unilateral PCA using a hybrid carpal arthrodesis bone plate applied dorsally have a good prognosis for return to work.CLINICAL RELEVANCE: Although this study has a small number of cases, this study provides subjective longer-term follow-up data than previously reported for working dogs that have undergone PCA. Owners should be warned that plate removal may be required in approximately 60% of dogs and additional expenditure should be planned for.

Ex vivo evaluation of carpal flexion after partial carpal arthrodesis in horses.

To determine degrees of flexion after arthrodesis of the antebrachiocarpal (ABC) joint, middle carpal (MC), and carpometacarpal (CMC) joints combined (MC/CMC), and carpometacarpal (CMC) joint alone. Ex vivo study. Forelimbs (n = 9) from 2- to 10-year-old Quarter Horses (5), Thoroughbred (2), and American Paint Horse (2). Using 2 locking compression plates, 3 partial carpal arthrodesis techniques were performed. Cables and deadweights were connected to limbs and each angle of flexion determined 3 times using a protractor and then averaged. Control measurements were obtained before and after arthrodesis, the techniques randomized with Latin square design. Descriptive data were analyzed with Levene's test, Q-Q plots, ANOVA, and Bonferroni test. Mean ± SD carpal flexion results were: controls 150° ± 8°, CMC arthrodesis 149° ± 9°, MC/CMC arthrodesis 43° ± 7.6°, and ABC arthrodesis 25° ± 6.3°. There was no significant reduction in flexion after a CMC arthrodesis compared with controls (P = .21), but there was after ABC (P < .001) and MC/CMC arthrodesis (P < .001), with the ABC arthrodesis significantly reduced compared with an MC/CMC arthrodesis (P < .001). Whereas CMC arthrodesis does not affect carpal flexion, CMC/MC and ABC arthrodesis markedly reduce the degree of carpal flexion.

Scaphocapitate Arthrodesis for Treatment of Scapholunate Instability in Manual Workers

To assess the long-term efficacy of scaphocapitate arthrodesis for treatment of chronic scapholunate instability in high-demand patients. We retrospectively analyzed the clinical and radiographic results of 20 manual workers who underwent scaphocapitate arthrodesis for chronic scapholunate instability at a mean follow-up of 10 years (range, 1-23 y). We measured range of motion and grip strength; pain on a scale of 0 to 5; Quick Disabilities of the Arm, Shoulder, and Hand score; and ability to return to work. We assessed radiographs for union, carpal height and alignment, signs of ulnar translation or radiocarpal arthritis, and hardware problems. At most recent follow-up, the arc of motion averaged 87° for flexion-extension and 41° for the radioulnar deviation. The postoperative average maximum grip strength was 21 kg, which was 60% of the opposite, normal wrist. Pain was significantly reduced. The average postoperative Quick Disabilities of the Arm, Shoulder, and Hand score was 19, and the return-to-work rate was 90%. Radiographic analysis showed union in all patients, improvement of carpal height and scaphoid angle, no evidence of ulnar translation, and a 30% rate of radiocarpal osteoarthritis. This report of long-term results demonstrates the efficacy of scaphocapitate limited carpal arthrodesis for the treatment of chronic rotatory subluxation of the scaphoid. We conclude that continued use of this procedure is warranted. Therapeutic IV.

Limited Carpal Arthrodeses for the Treatment of Wrist Osteoarthritis

The five main etiologies of wrist osteoarthritis are: a) Scapholunate instability leading to Scapholunate advanced collapse (SLAC) b) Scaphoid nonunion leading to Scaphoid Nonunion Advanced Collapse (SNAC) c) Distal radius intra-articular malunion d) Kienböck stage IV e) Chondrocalcinosis. The two last diseases are not post-traumatic. We discuss the advancement of arthritis in different stages, and the possibilities of limited carpal arthrodesis to fuse the joints involved in arthritis, taking care to preserve the intact joints. This retains a certain amount of motion at the wrist. It is always better to avoid total wrist arthrodesis which is less and less performed, due to the good long-term results of limited carpal arthrodeses.

OUTCOMES OF FOUR-CORNER ARTHRODESIS USING THE HUBCAPTM CIRCULAR PLATE

We present results of four-corner carpal arthrodesis with the Acumed Hubcap circular plate performed at our unit. Eight patients underwent eight procedures over five years, for scapholunate advanced collapse (five wrists) and scaphoid non-union advanced collapse (three wrists). Outcomes included range of motion, quickDASH scores, and visual analogue scores for satisfaction. At final follow-up, mean flexion-extension arc was 56°, mean radial-ulnar deviation 29° and mean quickDASH score was 23/100. Mean score for satisfaction was 7.7/10 (77%). Seven out of eight (87.5%) patients said they would have it done again, and would also recommend it to others. Radiological union was achieved in all cases. One screw broke in one arthrodesis without causing symptoms. The functional outcomes with our use of the Hubcap are comparable to those reported in literature to date with other circular plates (e.g. Spider plate). There were no non-unions, which is the main reported complication with these plates.

Biomechanical comparison of a novel castless arthrodesis plate with T-plate and cross pin techniques for canine partial carpal arthrodesis

To describe a novel canine castless partial carpal arthrodesis plate (par-CA) and its ex vivo biomechanical comparison with T-plate and cross pinning techniques for canine partial carpal arthrodesis. The three implant systems were applied to three cohorts of six forelimbs from Greyhounds euthanatized for reasons unrelated to the study. Intercarpal and carpometacarpal palmar fibrocartilage and ligaments were sectioned. Potentiometers were applied between the radial carpal and third metacarpal bones to measure micromotion, and limbs were loaded at 30% of bodyweight at 1 Hertz for 10,000 cycles on a servo-hydraulic universal testing machine. Following assessment of micromotion, limbs were loaded to failure at 20 mm/s and ultimate strength, ultimate displacement, and stiffness were measured. The T-plate (p <0.01) and par-CA (p <0.01) had reduced micromotion relative to the cross pin constructs but there was no significant difference between the control, T-plate and par-CA constructs. There was no significant difference in ultimate strength between constructs. Ultimate displacement was reduced in the plated constructs. Stiffness did not differ between constructs. The novel par-CA construct was biomechanically similar to the T-plate and both were superior to cross pins in resisting micromotion. There was no difference in load at failure between constructs. The par-CA plate permits radial and ulnar carpal bone compression, a more distal location of the plate to limit impingement, and placement of screws in two metacarpal bones; features which may offer clinical benefits over T-plate fixation.