4-corner Arthrodesis Research Articles

A Comparative Study of 2-Corner, 3-Corner, and 4-Corner Arthrodesis for Midcarpal Arthritis.

Four-corner fusion (4CF) is a common treatment for midcarpal arthritis; however, alternatives including 2-corner fusion (2CF) and 3-corner fusion (3CF) have been described. Limited literature suggests 2CF and 3CF may improve range of motion but have higher complication rates. Our objective is to compare function and patient-reported outcomes following 4CF, 3CF, and 2CF at our institution. Adult patients undergoing 4CF, 3CF, and 2CF from 2011 to 2021 who attended at least one follow-up were included. Four-corner fusion patients were compared with those who underwent either 3CF or 2CF using staple fixation. Outcomes include nonunion rate, reoperation rate, progression to wrist fusion, range of motion, and patient-reported pain, satisfaction, and Disabilities of the Arm, Shoulder, and Hand (DASH) scores. A total of 58 patients met inclusion criteria. There were 49 4CF and 9 2CF or 3CF patients. Nonunion rates, progression to wrist fusion, and repeat surgery for any indication were not significantly different among groups. Range of motion (flexion-extension, radial-ulnar deviation) and grip strength at postoperative visits were not significantly different. Significantly more 4CF patients required bone grafting. Pain, overall satisfaction, and DASH scores were similar. Although prior studies suggest increased risk of nonunion and hardware migration after 2CF/3CF, we did not observe higher complication rates compared with 4CF. Range of motion, strength, and patient-reported outcomes were similar. While 4CF is traditionally the procedure of choice for midcarpal fusion, we found that when using a staple fixation technique, 2CF and 3CF have comparable clinical and patient-reported outcomes yet decrease the need for autologous bone grafting.

Clinical Outcomes of Lunocapitate Arthrodesis: A Retrograde Single-Screw Approach.

A single-site retrospective study was designed to evaluate the clinical outcomes of single-screw lunocapitate arthrodesis (LCA) using a retrograde approach for the treatment of scapholunate advanced collapse (SLAC) wrist. We retrospectively identified 31 patients (33 cases) between September 2010 and December 2019 with SLAC wrist changes who were treated with single-screw LCA. Objective outcomes included time to fusion, union rate, range of motion, and grip and pinch strength recovery. Subjective outcomes included Disabilities of the Arm, Shoulder, and Hand (DASH) scores. We report on 33 cases (7 female), mean age 58.4 years (range: 41-85), with SLAC wrist who underwent LCA. Our cohort reported a 94% union rate and a 90-day mean time to fusion. Final active wrist range of motion was 38° dorsiflexion, 35° volarflexion, 17° radial deviation, 17° ulnar deviation, 82° pronation, and 83° supination (mean: 450.8 days). Final grip and pinch strengths recovered was 75% gross grip, 84% lateral pinch, and 75% precision pinch (mean: 379.0 days) compared with the contralateral side. The mean postoperative DASH score was 27 (mean: 1203.9 days). Two nonunions were observed. Two hardware complications occurred: one symptomatic screw and one screw fatigue fracture. We found retrograde single-screw LCA to be an effective salvage procedure for SLAC wrist. LCA is a less-taxing procedure, requires shorter operating time, and produces range of motion and grip and pinch strength recovery comparable to those of 4-corner arthrodesis. Furthermore, the viability of single-screw fixation may reduce hardware-related operative costs without compromising union rates.

Factors Associated With Unplanned Reoperation After 4-Corner Arthrodesis: A Study of 478 Wrists

The 4-corner arthrodesis (FCA) is a reliable, motion-sparing technique used to treat scapholunate advanced collapse and scaphoid nonunion advanced collapse arthritis, particularly in stage III wrists in which the capitolunate articulation is compromised. Surgical technique and patient-level variables may influence complications following FCA. We sought to evaluate the rate of complications in a large, combined database and manual chart review study. Current Procedural Terminology codes were used to search the United States Veteran's Health Administration corporate database to identify wrists treated with FCA over a 24-year period. A retrospective chart review was completed to collect data regarding scapholunate advanced collapse/scaphoid nonunion advanced collapse stage, implant used, the use of a bone graft, smoking status, and comorbidities for all patients undergoing an FCA. A multivariable cox proportional hazards regression was used to assess hazard ratios for reoperation. Incidence rates and the standard error of the mean for reoperation and conversion to total wrist fusion were calculated after grouping patients by 10-year age categories. A total of 478 wrists underwent FCA during the study period, with a mean follow-up of 63 months. Seventy-three (16%) wrists required reoperation. The most frequent secondary procedures included unplanned implant removal (8.2%), total wrist arthrodesis (4.6%), and revision FCA (1.7%). Positive smoking history increased the risk of reoperation, whereas posterior interosseous nerve neurectomy, arthritis stage, and fixation type did not have a statistically significant association with reoperation. Younger age demonstrated an increased incidence of overall reoperation and wrist fusion. The most common reason for reoperation after FCA was implant removal. Smoking history is associated with increased rates of reoperation and wrist arthrodesis. Knowledge of these factors may assist with accurately counseling and indicating patients for FCA. Therapeutic III.

Treatment Outcomes of All Arthroscopic 4-Corner Arthrodesis Techniques With 2 Headless Screws

Scaphoid excision with 4-corner arthrodesis is a safe procedure that relieves pain while also preserving the functional movements of the wrist. Different techniques have been described with successful results. In this study, we present the midterm clinical outcomes of 17 patients who underwent treatment with our arthroscopic 4-corner arthrodesis technique. Patients with at least 1 year of follow-up were included in our study. Preoperative and postoperative radiologic, functional, and clinical results were compared. Radiologic and clinical union were achieved in all patients. Significant improvement was observed in Quick Disabilities of the Arm, Shoulder, and Hand, Mayo Wrist Score, visual analog scale, and Patient-Rated Wrist Evaluation scores. Although wrist range of motion increased in the radioulnar plane, no clinically important change was observed in the flexion-extension arc. The patients were able to return to work in an average of 10 weeks. The arthroscopic 4-corner arthrodesis technique is a method with satisfactory outcomes. The main disadvantage of this procedure is that it requires a lengthy operative time, and both specific expertise and equipment. Therapeutic IV.

Scaphoidectomy and 4-corner arthrodesis with headless compression screws: results, complications and their treatment.

Scaphoidectomy and 4-corner arthrodesis is a common salvage surgery for degenerative wrist pathology. The purpose of this study was to evaluate the results of this procedure performed with headless compression screws, with a special focus on postoperative complications and their treatment. We assessed 36 wrists in 31 patients that were treated between 2009 and 2017. Mean follow-up was 5.2 years (range 2.9- 9.4). Pain was expressed on a Visual Analog Scale. The Quick Disabilities of the Arm, Shoulder and hand (qDASH) questionnaire and Michigan Hand Outcome Questionnaire (MHOQ) were used to assess patient functionality and satisfaction. Range of motion and grip strength of both wrists were measured. Radiographs of the operated wrist were evaluated. Mean pain score was 1.5 ± 2.3 with 19% of patients being completely free of pain also during activity. Mean qDASH was 44 ± 20 and mean MHOQ was 10 ± 5. Mean flexion-extension arc of the operated wrist was 69° and 61% of the contralateral wrist. Mean grip strength was 35kg and 89% of the opposite wrist. Non-union was observed in two patients. Two patients required hardware removal and in three patients a pisiformectomy was performed. Conversion to total wrist arthrodesis was needed in one patient. We observed postoperative complications in 28% of our patients. Most complications can successfully be treated with additional surgery. The presence of pisotriquetral arthritis should be assessed before surgery and treated with pisiform excision.

Four-Corner Arthrodesis With Differing Methods of Osteosynthesis: A Systematic Review

The purpose of this study was to compare the union rates and clinical outcomes of 4-corner arthrodesis with different methods of osteosynthesis. A systematic review of studies published in Ovid, Medline, Embase, and PubMed was conducted. Primary studies that reported clinical and radiographic results following 4-corner arthrodesis for scapholunate advanced collapse (SLAC), scaphoid nonunion advanced collapse (SNAC), or other types of wrist arthritis in human subjects were eligible. Biomechanical or cadaveric studies, case reports, studies that did not define and report a radiographic union rate, reviews and technical articles, studies that did not report the method of osteosynthesis, and studies that used multiple methods of osteosynthesis, but did not separate results for individual methods of osteosynthesis were excluded. Radiographic union rate, range of motion, and grip strength were analyzed. We identified and reviewed 291 full texts, selecting 57 studies for coding. The radiographic union rate did not significantly differ between studies using K-wire, screw, staple, nonlocking plate, metal locking plate, and radiolucent locking plate osteosynthesis. Fixation method significantly affected flexion, but pairwise comparison did not reveal any significant differences between individual groups. Grip strength as a percentage of the contralateral limb was significantly lower in studies with metal locking plate fixation compared to K-wire fixation (63.2% vs 82.6%). There were no other statistically significant differences between groups with respect to flexion, extension, radial deviation, ulnar deviation, and grip strength. All methods of osteosynthesis result in similar union rates, with no significant differences between methods. While there are some significant differences in range of motion and grip strength, these differences are unlikely to be clinically relevant. Therapeutic IV.

Proximal Row Carpectomy in Young Patients

There continues to be controversy regarding the treatment of early-stage arthritis of the wrist, particularly in young patients, because of the large number of techniques, the poor long-term results for many of these techniques, and the overall paucity of high-level scientific data. Proximal row carpectomy (PRC) and 4-corner arthrodesis (4CA) have been established as the mainstay motion-sparing surgical treatment options in cases of early scapholunate advanced collapse and scaphoid nonunion advanced collapse arthritis. However, there is marked controversy surrounding the best treatment option for younger patients with greater physical demands because of the questionable outcomes associated with these motion-sparing options in such patients1-9. Traditionally, many surgeons prefer 4CA over PRC for young, high-demand patients, in part because studies have suggested that young age and work status as a laborer are important risk factors for worse outcomes following PRC1,8. However, the concern for symptomatic nonunion and potential for radiolunate arthritis in 4CA, as well as the lack of medium to long-term comparative studies in this subset, make this recommendation controversial10. The wrist is accessed via the dorsal approach, creating a retinacular flap and a radially based ligament-sparing capsulotomy. The scaphoid, lunate, and triquetrum are then excised en bloc. The radioscapholunate ligament is protected. The capsule and retinaculum and then repaired. Alternatives to PRC include nonoperative treatment, 4CA, capitolunate arthrodesis, posterior and anterior interosseous neurectomies, total wrist arthroplasty, and total wrist arthrodesis. A recent study by Wagner et al. compared patients <45 years old who underwent either PRC or 4CA11. Overall, PRC and 4CA had similar complication rates, postoperative pain levels, wrist function, and long-term outcomes free of conversion to arthrodesis. Patients who underwent PRC had improved motion and fewer complications, whereas patients who underwent 4CA had slightly lower rates of radiocarpal arthritis. Therefore, in this technique article, we describe PRC for wrist arthritis in patients <45 years old.

Prosthetic Replacement of the Scaphoid Proximal Pole: Should It Be the Future?

Scaphoid proximal pole fractures with avascular necrosis represent a complex surgical problem. Many reconstruction techniques are based on osteosynthesis with a vascularized or nonvascularized bone graft. These procedures do not allow early mobilization and therefore sometimes lead to unsatisfying functional results. In some cases, it is possible to perform a scaphoid hemiarthroplasty using a pyrocarbon implant (adaptive proximal scaphoid implant [APSI]) in place of the necrotic proximal pole, allowing an early mobilization and delaying palliative treatments such as 4-corner arthrodesis or proximal row carpectomy. In this study, we reviewed all patients who had undergone a scaphoid hemiarthroplasty using APSI in our institutions from 1999 to 2017; the F.U. was performed through radiographic, clinical, and subjective (Disabilities of the Arm, Shoulder, and Hand) analysis. The performances of scaphoid proximal pole implants are encouraging; radiographic, clinical, and subjective outcomes were good, and the functional recovery proved to be fast and reliable over time. This study reports our experience in the use of APSI implants, which proved to be a good alternative to traditional techniques for treating avascular necrosis of the proximal pole, still allowing further surgical steps in case of clinical worsening over time (wrist osteoarthritis). These patients are usually young and present high functional demands. Our experience is promising, but we believe that further evaluation over time will be needed.

Reconstruction of the Proximal Scaphoid With a Medial Femoral Trochlea Osteochondral Graft: Minimum 2-Year Results

To report the clinical and radiological outcomes after medial femoral trochlear (MFT) osteochondral graft for the salvage of proximal scaphoid fractures with a minimum 2-year follow-up. A retrospective review was performed of patients with comminuted fractures of the proximal scaphoid treated by excision of the proximal pole and replacement with free vascularized MFT osteochondral graft. Demographic data, objective and radiographic measurements, and patient-reported outcome measures of the upper limb and knee were collected. Pain was assessed by completion of a visual analog scale (VAS). Between February 2014 and May 2015, 12 MFT osteochondral grafts were performed. Eight patients were available for follow-up at a mean of 34 months (range, 28-39 months). The mean range of wrist flexion was 31° (range, 15°-60°), extension was 34° (range, 5°-60°), radial deviation was 9° (range, 0°-20°), ulnar deviation was 28° (range, 10°-45°) and grip strength was 42 kg (range, 25-53 kg). The median wrist pain, as measured by VAS, was 0.7 (mean, 1.3; range, 0-6). The average follow-up scapholunate, radiolunate, and radioscaphoid angles were 58.9° (range, 44°-93°), 12.9° (range, 0°-30°), and 46.0° (range, 35°-63°), respectively. The mean Disabilities of the Arm, Shoulder, and Hand (DASH) score was 13.9 (range, 3-43) and Patient Rated Wrist Evaluation (PRWE) score was 22.4 (range, 2-68). The mean postoperative Oxford Knee Score was 42 (range, 14-48). One patient suffered notable knee pain at 37-month follow-up. One patient suffered notable pain on the radial side of the wrist and underwent scaphoid excision and 4-corner arthrodesis. Replacement of the fragmented proximal scaphoid by MFT graft is an alternative to other salvage options and most patients can expect pain relief and acceptable wrist motion. These results need to be balanced against the potential for donor-site morbidity. Therapeutic V.

Dry arthroscopic 4-corner arthrodesis and other refinements to stay within a tourniquet time

4-corner arthrodesis is a widely implanted procedure to treat degenerated joints in the wrist such as SLAC and SNAC stage II and III. Arthroscopy in combination with headless cannulated screws, permits reproducing the same intervention with the advantages of a minimally invasive surgery. This technique has already been published in the past supported by the early experience in this new exciting field. The purpose of this paper is to present new technical refinements collected over the years in order to speed up the surgery while obtaining optimum results. In this paper we also present extreme scenarios solved by combining the scope with cannulated screws.

Four-Corner Arthrodesis Versus Proximal Row Carpectomy for Scapholunate Advanced Collapse: A Systematic Literature Review and Meta-analysis.

Scapholunate advanced collapse (SLAC) of the wrist is one of the most common patterns of degenerative arthritis in the wrist. Surgical intervention is warranted for individuals with symptomatic SLAC and degenerative disease that affects the radioscaphoid joint. The most popular options for motion-preserving reconstruction and treatment of this disease include 4-corner arthrodesis and proximal row carpectomy. The purpose of this article was to conduct a systematic literature review and meta-analysis to identify any differences in the clinical outcomes of 4-corner arthrodesis and proximal row carpectomy for the treatment of SLAC. An electronic literature search of PubMed, Embase, OVID, and the Cochrane Library was conducted to identify studies evaluating the clinical outcomes of 4-corner arthrodesis versus proximal row carpectomy for the treatment of SLAC. Primary outcome measures included flexion/extension range of motion, grip strength, and level of pain. Eight studies encompassing 311 patients met the inclusion criteria for the meta-analysis. Our meta-analysis indicated that when compared with 4-corner arthrodesis, patients who underwent proximal row carpectomy had statistically significantly increased flexion/extension range of motion by 6.2 degrees, significantly increased grip strength by 1.52%, and reduced level of pain by 0.3. This study demonstrated that in comparative studies, there was a statistical difference favoring proximal row carpectomy to 4-corner arthrodesis for the treatment of SLAC. Although these differences were statistically significant, they remain very small and lack clinical relevance. This study further supports that both of these treatment options are equivalent for the treatment of this disease. Although not clinically significant, compared with 4-corner arthrodesis, patients treated with proximal row carpectomy had increased range of motion, increased grip strength, and decreased pain. Limitations to these findings are the small number of studies available and the increased heterogeneity between the studies. Further studies need to be conducted to confirm these findings.

Risk of Total Wrist Arthrodesis or Reoperation Following 4-Corner Arthrodesis or Proximal Row Carpectomy for Stage-II SLAC/SNAC Arthritis: A Propensity Score Analysis of 502 Wrists.

For stage-II scapholunate advanced collapse (SLAC) and scaphoid nonunion advanced collapse (SNAC) patterns of wrist arthritis, the optimal method of surgical treatment remains unclear. Previous literature has demonstrated similar clinical outcomes between proximal row carpectomy (PRC) and 4-corner arthrodesis (FCA), making the risk of reoperation a focus of particular interest. In the present study, the primary null hypothesis was that there would be no difference in the rate of conversion to total wrist arthrodesis between PRC and FCA. Additionally, we hypothesized that the rate of secondary surgical procedures would be similar between the 2 procedures. The national Veterans Health Administration Corporate Data Warehouse was utilized to identify 2,449 patients who underwent either PRC or FCA between 1992 and 2016. With use of operative reports to identify the arthritis pattern, only cases of stage-II SLAC/SNAC were included. All complications and subsequent surgical procedures were confirmed by manual chart review. Propensity score analyses with matching weights were utilized to balance the PRC and FCA cohorts. The rates of conversion to wrist arthrodesis and secondary surgical procedures were calculated. Of the 1,168 patients with stage-II SLAC/SNAC arthritis, 933 wrists underwent PRC and 257 wrists underwent FCA. Ten-year survival free of total wrist arthrodesis in the matching PRC (251 procedures) and FCA (251 procedures) cohorts was 94.3% (95% confidence interval [CI], 92.3% to 96.3%) and 94.1% (95% CI, 90.8% to 97.4%), respectively. Survival free of a secondary surgical procedure other than wrist arthrodesis was 99.7% (95% CI, 99.3% to 100.0%) for PRC and 83.5% (95% CI, 78.2% to 88.8%) for FCA. PRC and FCA demonstrated similarly low rates of conversion to total wrist arthrodesis. In contrast, the rate of secondary surgical procedures following FCA was significantly higher compared with PRC. Given the historically similar clinical outcomes between PRC and FCA, the results of the present study show that PRC may be a preferable treatment for stage-II SLAC/SNAC wrist arthritis. Therapeutic Level III. See Instructions for Authors for a complete description of levels of evidence.

Surgical Treatment of Wrist Arthritis in Young Patients.

Surgical treatment of wrist arthritis in the younger patient population remains a challenging issue, and various surgical options need to be carefully considered for each patient. Proximal row carpectomy and 4-corner arthrodesis have proven to be reliable options for reducing pain and restoring adequate function in most young high-demand patients if the lunate facet is spared. Selective neurectomy has proven to be a promising stand-alone or complementary procedure for the treatment of pain that is associated with wrist arthritis in patients of all ages, with spared motion and the opportunity to perform additional procedures if pain continues. Alternative procedures, including capitolunate arthrodesis, total wrist arthrodesis, radial styloidectomy, total wrist arthroplasty, and wrist hemiarthroplasty, have considerable strengths and weaknesses and need to be studied further in younger patients.

Factors Associated With Reoperation and Conversion to Wrist Fusion After Proximal Row Carpectomy or 4-Corner Arthrodesis

Proximal row carpectomy (PRC) and 4-corner arthrodesis (FCA) are common salvage procedures for the treatment of scapholunate advanced collapse and scaphoid nonunion advanced collapse. This study aimed to assess rates of reoperation and conversion to wrist fusion and to assess the factors associated with reoperation and conversion to wrist fusion for patients treated with PRC and FCA. A retrospective chart review was performed evaluating 266 adult patients undergoing PRC or FCA at a single institutional system from 2002 to 2016. Demographic data, patient- and injury-specific data, reoperation and conversion rates, and complications were collected. Potential factors associated with reoperation or wrist fusion were evaluated using a bivariate, followed by a multivariable, analysis. Reoperation was more commonly performed in FCA (34%) than in PRC (11%) (odds ratio [OR], 3.4; 95% confidence interval [95% CI], 1.7-6.8) and occurred at a shorter postoperative interval. In a multivariable analysis for reoperation, manual labor was associated with reoperation in patients undergoing FCA (OR, 5.4; 95% CI, 1.5-19.1). In those undergoing PRC, anterior interosseous nerve (AIN) and/or posterior interosseous nerve (PIN) neurectomy was associated with a lower rate of reoperation (OR, 0.18; 95% CI, 0.06-0.57). In a multivariable analysis for conversion to wrist arthrodesis, intraoperative AIN and/or PIN neurectomy (OR, 0.18; 95% CI, 0.06-0.57) was associated with a lower rate of conversion to wrist fusion, and smoking (OR, 4.9; 95% CI, 1.8-13.5) was associated with a higher rate of conversion to wrist fusion. In the subanalysis of patients who underwent PRC, only AIN and/or PIN neurectomy was associated with lower rates of conversion to wrist arthrodesis (OR, 0.15; 95% CI, 0.04-0.56). In our cohort, we observed that AIN and/or PIN neurectomy reduced the risk of reoperation and conversion to wrist arthrodesis after PRC. Smoking increased the odds of conversion to wrist arthrodesis in the combined PRC/FCA cohort; however, it is unclear whether this was due to smoking itself or whether the indications for PRC or FCA were affected, leading to this result. Prognostic IV.

Capitolunate Arthrodesis: A Systematic Review

To compile and review the indications, outcomes, and complications of capitolunate arthrodesis (CLA). We performed a literature search identifying 33 articles, 6 of which met inclusion criteria, including 80 patients. Included publications contained the results of CLA with minimum 12-month follow-up between 2000 and 2018. Data were pooled and analyzed focusing on the primary outcomes of union and complications. Average age of patients was 48 years (range, 22-86 years), median follow-up was 34 months (range, 12-198 months), and most common indication was scaphoid nonunion advanced collapse (59%). Nearly half underwent a concomitant triquetrum excision (49%). Most patients were pain-free (78%) and returned to work (92%). Grip strength and visual analog pain scale both improved after CLA. Whereas 96% fused within a reported 42 to 210 days (median, 70 days), 11% of patients had complications including nonunion (3.8%) and loose hardware (6.3%). The reoperation rate was 14%, including wrist arthrodeses and wrist arthroplasty. Capitolunate arthrodesis is a feasible option for scapholunate advanced collapse and scaphoid nonunion advanced collapse wrists with complications similar to those encountered in 4-corner arthrodesis. Therapeutic IV.

Comparison of Direct Surgical Costs for Proximal Row Carpectomy and 4-Corner Arthrodesis

Comparison of Direct Surgical Costs for Proximal Row Carpectomy and 4-Corner Arthrodesis

Proximal Row Carpectomy and 4-Corner Arthrodesis in Patients Younger Than Age 45 Years

To examine the long-term outcome of patients aged less than 45 years who underwent either proximal row carpectomy (PRC) or 4-corner arthrodesis (4CA) for wrist arthritis. We reviewed a retrospective cohort of 89 patients aged less than 45 years who underwent either 4CA (n= 51) or PRC (n= 38) for wrist arthritis. Mean follow-up was 11 years in the 4CA group and 18 years in the PRC group. Overall, there were no differences between groups in the need for revision surgery. Complications included 6 nonunions in the 4CA group (12%), 1 infection in each group, and 11 patients who experienced radiocarpal impingement (8 4CA and 3 PRC). There was no difference in the number of patients reporting moderate or severe pain between the PRC and 4CA groups. Mean flexion-extension arc was 54° after 4CA, compared with 73° after PRC. Patients who underwent 4CA had slightly improved grip strength (65% of the opposite side) compared with those who had PRC (54%). Mean postoperative Disabilities of the Arm, Shoulder, and Hand questionnaire scores were 32 versus 19 (PRC vs 4CA) and patient-rated wrist evaluation scores were 27 versus 28 (PRC vs 4CA). Comparing radiographic arthritis, the 10-year outcome, free of moderate/severe arthritis for the PRC and 4CA groups, was 70% and 71%, respectively. Both PRC and 4CA represent a good surgical option for young patients with wrist arthritis, with similar complication rates, postoperative pain levels, wrist function, and long-term outcomes free of arthrodesis. Proximal row carpectomy has improved motion and fewer complications. Therapeutic IV.

The Effect of Capitate Position on Coronal Plane Wrist Motion After Simulated 4-Corner Arthrodesis

The objective of this study was to examine the effect of altering the capitolunate relationship on coronal-plane wrist motion after scaphoidectomy and simulated 4-corner arthrodesis. Two positions of different capitolunate alignments were compared: "anatomic" (unchanged from pre-fusion) and "lunate-covered" (capitate translated to cover the lunate). We hypothesized that wrist resting posture would be altered and radial-ulnar motion would diminish after 4-corner arthrodesis in the lunate-covered position when compared with normal wrists. Six human cadaveric limbs were disarticulated at the elbow and mounted on a custom jig. The resting position of the wrist was recorded with no load applied, followed by a load of 44 N applied to the flexor carpi radialis, extensor carpi radialis longus, and extensor carpi radialis brevis tendons to simulate radial deviation and to the flexor carpi ulnaris and extensor carpi ulnaris tendons to simulate ulnar deviation. Scaphoidectomy was performed and 2 methods of 4-corner arthrodesis with different capitolunate coronal alignments were studied in random order. Range of motion was compared using one-way analysis of variance and Bonferroni correction. The "lunate covered" wrist demonstrated significantly greater radial resting posture than that of the preoperative wrist. Under a 44 N load, the lunate-covered position had significantly greater radial motion than the preoperative radial motion. Wrists fused in the "anatomic" position did not differ significantly from the preoperative wrists in posture or range of motion. In this cadaveric model, complete covering of the capitate head by the lunate placed the wrist in increased radial deviation compared with the anatomic posture. Changes induced in the resting tension of the extrinsic wrist ligaments serve as a reasonable explanation for the increased radial posture and motion. In a clinical setting, these changes may affect postoperative wrist posture and function. Maintaining anatomic lunate position leads to preservation of greater wrist motion and anatomic alignment in a patient undergoing 4-corner arthrodesis.

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.

Three-Corner Arthrodesis With Scaphoid and Triquetrum Excision for Wrist Arthritis

To report the clinical and radiographic results of a consecutive series of patients who underwent the 3-corner arthrodesis (3CA) (arthrodesis of capitate, hamate, and lunate with scaphoid and triquetrum excision) procedure for wrist arthritis. This was a retrospective study of 30 consecutive patients who underwent a 3CA between 1994 and 2008. The indications were painful wrist osteoarthritis due to stage 2 or 3 scapholunate advanced collapse, scaphoid nonunion advanced collapse, or scaphoid chondrocalcinosis advanced collapse wrists. The clinical assessment consisted of range of motion, grip strength, and the Disabilities of the Arm, Shoulder, and Hand and Patient-Rated Wrist Evaluation scores. The radiographic assessment parameters consisted of bone fusion, carpal height and translation, lunate tilt, and appearance of the radiolunate joint space. The average follow-up was 6 years (± 4 years). The arthrodesis was performed with staples, 2 screws, or a plate and screws. Grip strength was 72% of the contralateral side. The mean range of motion in flexion-extension arc and ulnar-radial deviation arc was 70° and 36°, respectively. The mean Disabilities of the Arm, Shoulder, and Hand and the Patient-Rated Wrist Evaluation scores were 17 (± 11) and 22 (± 24), respectively. The fusion incidence was 90% (27 of 30). The mean difference of radiolunate angle on preoperative and postoperative radiographs was 8° (16°-8° in dorsal direction). The radiolunate joint space had narrowed in 1 patient. Six surgical revisions (20%) were necessary owing to dorsal pain in patients operated using plates, staples, or excessively long screws. Three-corner arthrodesis results are comparable with 4-corner arthrodesis and proximal row carpectomy. We feel that it is simpler technically than 4-corner arthrodesis. Although 3CA is more complex than proximal row carpectomy, it preserves the native radiolunate joint. Complications that can be attributed to the dorsal fixation hardware (particularly staples and plates) were noteworthy. Therapeutic IV.